TWI566947B - Heat release element, electronic device and battery - Google Patents

Description

Heat release member, electronic component and battery

The present invention relates to a heat releasing member, an electronic component, and a battery.

A graphite sheet obtained by heat-treating a polymer film exhibits excellent thermal conductivity, and thus is used as a heat conductor (Patent Document 1).

In recent years, electronic devices have increased in heat generation due to high performance and high functionality. Therefore, it is required to use a heat conductor having superior heat release characteristics in the device. As such a heat conductor, a method of using a laminate in which a graphite sheet and a metal sheet are bonded by an adhesive is disclosed (Patent Documents 2 to 5).

Patent Document 3 describes a method in which a rubber-like elastic adhesive or an fluorenke-based thermal conductive adhesive is used as an adhesive. In Patent Document 4, it is described that a conductive filler such as silver, gold or copper is used. The method of the subsequent agent. Further, Patent Document 5 describes a method of using an acrylic adhesive.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 11-21117

[Patent Document 2] Japanese Patent Laid-Open Publication No. 2001-144237

[Patent Document 3] Japanese Patent Laid-Open No. Hei 10-247708

[Patent Document 4] Japanese Patent Laid-Open Publication No. 2004-23066

[Patent Document 5] Japanese Patent Laid-Open Publication No. 2009-280433

In the conventional heat conductor (laminate), there is a case where the adhesion strength between the graphite sheet and the metal sheet is poor.

Further, the layer containing the adhesive (the subsequent layer) generally has a small thermal conductivity, and as the thickness of the layer becomes thick, the thermal resistance of the laminated body in the lamination direction becomes large. Therefore, it is required to use an adhesive layer having a thickness as thin as possible.

However, the adhesive layer described in the above-mentioned patent document has a poor adhesion strength between the graphite sheet and the metal sheet. Therefore, if the thickness of the adhesive layer is not increased, there is a case where a heat conductor that can be used in an electronic device or the like cannot be obtained. . The laminate having the thickness of the subsequent layer has a large thermal resistance in the lamination direction of the laminate, and has poor heat dissipation characteristics.

The present invention has been made in view of such a problem, and an object thereof is to provide a heat releasing member having an adhesive layer having a metal layer and a graphite layer which are excellent in adhesion strength and thin in thickness.

The inventors of the present invention have conducted intensive studies to solve the above problems, and as a result, have found that the above problems can be solved by the following heat releasing members, which comprise a metal layer and a graphite layer laminated via a specific adhesive layer. Laminated body.

[1] A heat releasing member comprising a laminate in which a metal layer and a graphite layer are laminated via an adhesive layer, the adhesive layer being formed of a composition containing a polyvinyl acetal resin.

[2] The heat releasing member according to [1], wherein the composition further comprises a thermally conductive filler.

[3] The heat releasing member according to [1] or [2], wherein the polyvinyl acetal resin comprises the following structural unit A, structural unit B, and structural unit C,

(In structural unit A, R is independently hydrogen or alkyl)

[4] The heat releasing member according to [3], wherein the polyvinyl acetal resin further comprises the following structural unit D,

(In Structural Unit D, R ^{1 is} independently hydrogen or an alkyl group having 1 to 5 carbon atoms).

[5] The heat releasing member according to [3] or [4], wherein R in the structural unit A is hydrogen or an alkyl group having 1 to 3 carbon atoms.

[6] The heat releasing member according to any one of [1] to [5] wherein the laminated layer has a thermal conductivity of 0.05 W/m in a lamination direction. K~50W/m. K.

[7] The heat releasing member according to any one of [1] to [6] wherein the thickness of the adhesive layer is 0.05 μm to 10 μm.

[8] The heat releasing member according to any one of [2], wherein the adhesive layer contains 1 vol% to 80 vol% of a thermally conductive filler with respect to 100 vol% of the adhesive layer.

[9] The heat releasing member according to any one of [2], wherein the thermally conductive filler comprises a metal powder, a metal oxide powder, a metal nitride powder, and a metal carbide powder. At least 1 powder of the group.

[10] The heat releasing member according to [9], wherein the thermally conductive filler comprises at least selected from the group consisting of aluminum nitride powder, alumina powder, zinc oxide powder, magnesium oxide powder, tantalum carbide powder, tungsten carbide powder, and aluminum powder. And copper powder At least one powder of the group formed.

[11] The heat releasing member according to [9], wherein the thermally conductive filler has an average diameter of 0.001 μm to 30 μm.

[12] The heat releasing member according to any one of [2] to [8] wherein the heat conductive filler is a filler containing a carbon material.

[13] The heat releasing member according to [12], wherein the thermally conductive filler comprises at least one powder selected from the group consisting of graphite powder, carbon nanotubes, and diamond powder.

[14] The heat releasing member according to any one of [1] to [13], wherein a thermal conductivity of the graphite layer in a substantially vertical direction with respect to a lamination direction of the laminated body is 250 W/m. K~2000W/m. K.

[15] The heat releasing member according to any one of [1] to [14] wherein the graphite layer has a thickness of 15 μm to 600 μm.

[16] The heat releasing member according to any one of [1] to [15] wherein the thickness of the metal layer is 0.01 to 100 times the thickness of the graphite layer.

[17] The heat releasing member according to any one of [1], wherein the metal layer is an alloy containing at least any one of silver, copper, aluminum, nickel, and at least one of the metals. A layer of at least one metal of the group formed.

[18] The heat releasing member according to any one of [1], wherein the metal layer is a group comprising an alloy of copper, aluminum, and at least any one of the metals. A group of at least one metal layer.

[19] The heat releasing member according to any one of [1] to [18] wherein The heat radiation member includes at least two metal layers including one or more metals of a group consisting of copper, aluminum, and an alloy of at least one of the metals including at least one of the metals, at least one of the metal layers 2 are different layers.

[20] The heat releasing member according to any one of [1] to [19] wherein a resin layer is provided on one or both sides of the outermost layer of the heat releasing member.

[21] The heat releasing member according to [20], wherein the resin layer contains a filler containing an inorganic compound.

[22] The heat releasing member according to [20] or [21] wherein the resin layer comprises: a group selected from the group consisting of an acrylic resin, an epoxy resin, an alkyd resin, an amine ester resin, and a nitrocellulose. At least one resin selected from the group consisting of at least one compound selected from the group consisting of alumina, ceria, cordierite, mullite, tantalum carbide, and magnesium oxide.

[23] An electronic component comprising the heat releasing member according to any one of [1] to [22].

[24] A battery comprising the heat releasing member according to any one of [1] to [22].

According to the present invention, it is possible to provide a heat releasing member having a thinner backing layer and a high bonding strength between the metal layer and the graphite layer.

Moreover, by the present invention, it is possible to provide a heat releasing member having excellent workability and/or bendability.

Further, according to the present invention, it is possible to provide a battery or an electronic component which can be reduced in weight and size.

"heat release component"

The heat radiation member of the present invention includes a laminate in which a metal layer and a graphite layer are laminated via an adhesive layer, and the adhesive layer is formed of a composition containing a polyvinyl acetal resin.

Since the laminated body has a metal layer and a graphite layer laminated via the adhesive layer, the metal layer of the heat releasing member of the present invention including the laminated body has a high bonding strength to the graphite layer, and is excellent in workability and bendable.

<Next layer>

The adhesive layer is not particularly limited as long as it is formed of a composition containing a polyvinyl acetal resin, and may be formed of a composition other than the resin, depending on the type of the metal layer, and the like. Further, a thermally conductive filler, an additive, and a solvent are contained within a range that does not impair the effects of the present invention.

By using such an adhesive layer, it is possible to obtain a heat releasing member which is excellent in adhesion strength between the metal layer and the graphite layer and which is excellent in bending, toughness, flexibility, heat resistance and impact resistance.

[Polyvinyl acetal resin]

The polyvinyl acetal resin is not particularly limited, and is excellent in toughness, heat resistance, and impact resistance, and is preferably a laminate having excellent thickness and adhesion to a metal layer or a graphite layer. A resin comprising the following structural unit A, structural unit B, and structural unit C.

[Chemical 5]

The structural unit A is a structural unit having an acetal moiety, and can be formed, for example, by reaction of a continuous polyvinyl alcohol chain unit with an aldehyde (R-CHO).

R in the structural unit A is independently hydrogen or an alkyl group. If R is a bulky group (for example, a hydrocarbon group having a large carbon number), the softening point of the polyvinyl acetal resin tends to decrease. Further, the polyvinyl acetal resin in which R is a bulky base has high solubility in a solvent, but on the other hand, it has poor chemical resistance. Therefore, the R is preferably hydrogen or an alkyl group having 1 to 5 carbon atoms, and more preferably hydrogen or a 1-3 carbon atom from the viewpoint of the toughness of the obtained subsequent layer, and further preferably. It is hydrogen or propyl, and it is particularly preferable in terms of heat resistance and the like.

[Chemistry 7]

It is preferable that the polyethylene acetal resin includes the following structural unit D in addition to the structural unit A to the structural unit C, from the viewpoint of obtaining an adhesive layer excellent in adhesion strength to the metal layer or the graphite layer.

In the structural unit D, R ^{1 is} independently hydrogen or an alkyl group having 1 to 5 carbon atoms, preferably hydrogen or an alkyl group having 1 to 3 carbon atoms, more preferably hydrogen.

The total content of the structural unit A, the structural unit B, the structural unit C and the structural unit D in the polyvinyl acetal resin is preferably from 80 mol% to 100 mol% based on all the structural units of the resin. Examples of other structural units which may be contained in the polyvinyl acetal resin include an ethylene acetal chain unit other than the structural unit A (wherein R in the structural unit A is a hydrogen or a structural unit other than an alkyl group), and the following molecules An acetal unit, and a hemiacetal unit described below. The content of the ethylene acetal chain unit other than the structural unit A is preferably less than 5 mol% based on all the structural units of the polyvinyl acetal resin.

(R in the intermolecular acetal unit is synonymous with R in the structural unit A)

(R in the hemiacetal unit is synonymous with R in the structural unit A)

In the polyvinyl acetal resin, the structural unit A to the structural unit D may be arranged in a regular manner (block copolymer, alternating copolymer, etc.), or Randomly arranged (random copolymer), preferably randomly arranged.

As each structural unit in the polyvinyl acetal resin, it is preferred that the content of the structural unit A is 49.9 mol% to 80 mol%, and the content ratio of the structural unit B is relative to all structural units of the resin. From 0.1 mol% to 49.9 mol%, the content of the structural unit C is from 0.1 mol% to 49.9 mol%, and the content of the structural unit D is from 0 mol% to 49.9 mol%. More preferably, the content of the structural unit A is from 49.9 mol% to 80 mol%, and the content of the structural unit B is from 1 mol% to 30 mol%, based on all the structural units of the polyvinyl acetal resin, and the structural unit C The content ratio is 1 mol% to 30 mol%, and the content of the structural unit D is 1 mol% to 30 mol%.

From the viewpoint of obtaining a polyvinyl acetal resin excellent in chemical resistance, flexibility, abrasion resistance, and mechanical strength, the content of the structural unit A is preferably 49.9 mol% or more.

When the content of the structural unit B is 0.1 mol% or more, the solubility of the polyvinyl acetal resin in a solvent is improved, which is preferable. In addition, when the content of the structural unit B is 49.9 mol% or less, the chemical resistance, flexibility, abrasion resistance, and mechanical strength of the polyvinyl acetal resin are less likely to be lowered, which is preferable.

The structural unit C preferably has a content of 49.9 mol% or less from the viewpoint of solubility of the polyvinyl acetal resin in a solvent or adhesion of the obtained adhesive layer to a metal layer or a graphite layer. Further, in the production of the polyvinyl acetal resin, when the polyvinyl alcohol chain is acetalized, the structural unit B and the structural unit C have a balanced relationship, and therefore, the structural unit C is preferable. The content ratio is 0.1 mol% or more.

From the viewpoint of obtaining an adhesive layer excellent in adhesion strength to a metal layer or a graphite layer, etc., it is preferred that the content of the structural unit D is in the above range.

The content ratio of each of the structural unit A to the structural unit C in the polyvinyl acetal resin can be measured based on JIS K 6728 or JIS K 6729.

The content ratio of the structural unit D in the polyvinyl acetal resin can be measured by the method described below.

The polyvinyl acetal resin was heated at 80 ° C for 2 hours in a 1 mol/l sodium hydroxide aqueous solution. By this operation, sodium is added to the carboxyl group to obtain a polymer having -COONa. After extracting excess sodium hydroxide from the polymer, it is dehydrated and dried. Thereafter, carbonization was carried out to carry out atomic absorption analysis, and the amount of addition of sodium was determined and quantified.

Further, when the content ratio of the structural unit B (vinyl acetate chain) is analyzed, the structural unit D is quantified as a vinyl acetate chain, and thus the content ratio of the structural unit B measured based on the JIS K 6728 or JIS K6729 is reduced. The content ratio of the structural unit D to be quantified is corrected, and the content ratio of the structural unit B is corrected.

The weight average molecular weight of the polyvinyl acetal resin is preferably from 5,000 to 300,000, more preferably from 10,000 to 150,000. When a polyvinyl acetal resin having a weight average molecular weight within the above range is used, a heat releasing member can be easily produced, and a heat releasing member excellent in moldability and bending strength can be obtained, which is preferable.

The weight average molecular weight of the polyvinyl acetal resin may be appropriately selected depending on the intended purpose, and the temperature at which the heat releasing member is produced may be suppressed. In view of the low heat release member having a high thermal conductivity, it is more preferably 10,000 to 40,000; and more preferably, it is 50,000 to 150,000 from the viewpoint of obtaining a heat releasing member having a high heat resistance temperature.

The weight average molecular weight of the polyvinyl acetal resin in the present invention can be measured by the GPC method. The specific measurement conditions are as follows.

Detector: 830-RI (manufactured by JASCO Corporation)

Oven: West End Company manufactures NFL-700M

Separation column: Shodex KF-805L × 2

Pump: PU-980 (manufactured by JASCO Corporation)

Temperature: 30 ° C

Carrier: tetrahydrofuran

Standard sample: polystyrene

The Oswald viscosity of the polyvinyl acetal resin is preferably 1 mPa. s~100mPa. s. When a polyvinyl acetal resin having an Oswald viscosity in the above range is used, a heat releasing member can be easily produced, and a heat releasing member excellent in toughness can be obtained, which is preferable.

The Oswald viscosity can be measured by using a solution obtained by dissolving 5 g of a polyvinyl acetal resin in 100 ml of dichloroethane at 20 ° C using an Ostwald-Cannon Fenske Viscometer.

Specific examples of the polyvinyl acetal resin include polyvinyl butyral, polyvinyl formal, polyethylene acetal, and derivatives thereof. In view of the adhesion to the graphite layer and the heat resistance of the subsequent layer, polyvinyl formal is preferred.

As the polyvinyl acetal resin, the resin may be used singly or in combination of two or more kinds of structural units in the order of bonding or the number of bonds.

The polyvinyl acetal resin can be obtained by synthesis or a commercially available product.

The method of synthesizing the resin including the structural unit A, the structural unit B, and the structural unit C is not particularly limited, and examples thereof include those described in JP-A-2009-298833. Further, the method of synthesizing the resin including the structural unit A, the structural unit B, the structural unit C, and the structural unit D is not particularly limited, and examples thereof include those described in JP-A-2010-202862.

As a commercial item of the polyvinyl acetal resin, polyvinyl acetal may, for example, Vinylec C, Vinylec K (manufactured by JNC), and polyvinyl butyral may be exemplified by Denka Butyral 3000- K (manufactured by Electric Chemical Industry Co., Ltd.) and the like.

[thermally conductive filler]

The adhesive layer is provided with a thermally conductive filler to improve the thermal conductivity of the adhesive layer, and in particular to improve the thermal conductivity of the laminate in the lamination direction.

By using an adhesive layer containing a thermally conductive filler, it is possible to provide a heat releasing member which is thin in thickness of the adhesive layer, excellent in heat release characteristics and workability, high in adhesion strength between the metal layer and the graphite layer, and excellent in workability and bendable. Further, it is possible to provide an electronic component which can sufficiently remove heat generated from the heat generating body, can be reduced in weight, and can be reduced in size, or can suppress a battery or the like which is caused by heat generation even at a high energy density.

In the present invention, the "layering direction of the laminated body" means, for example, the metal layer 2, the subsequent layer 3, and the graphite layer 4 in the longitudinal direction, that is, the laminated body (heat releasing member) 1 in FIG. direction. Specifically, it means the direction from the metal layer 2 toward the adhesion layer 3 and the graphite layer 4, or the direction from the graphite layer 4 toward the adhesion layer 3 and the metal layer 2.

The thermally conductive filler is not particularly limited, and examples thereof include metal or metal compounds such as metal powder, metal oxide powder, metal nitride powder, metal hydroxide powder, metal oxynitride powder, and metal carbide powder. Fillers, fillers containing carbon materials, and the like.

Examples of the metal powder include powders of metals such as gold, silver, copper, aluminum, and nickel, and alloys containing the metals. Examples of the metal oxide powder include alumina powder, zinc oxide powder, magnesium oxide powder, cerium oxide powder, silicate powder, and the like. Examples of the metal nitride powder include aluminum nitride powder, boron nitride powder, tantalum nitride powder, and the like. Examples of the metal hydroxide powder include aluminum hydroxide powder, magnesium hydroxide powder, and the like. Examples of the metal oxynitride include aluminum oxynitride powder, and the metal carbide powder may, for example, be tantalum carbide powder or tungsten carbide powder.

Preferred from the viewpoints of thermal conductivity and ease of availability, aluminum nitride powder, alumina powder, zinc oxide powder, magnesium oxide powder, tantalum carbide powder, and tungsten carbide powder are preferred.

Further, in the case of using a filler containing a metal or a metal compound as the above-mentioned thermally conductive filler, it is preferred to use a filler containing a metal of the same kind as the metal constituting the metal layer.

If a filler containing a metal or a metal compound different from the metal constituting the metal layer is used as the thermal conductive filler, it exists in the metal layer and A situation occurs in which a local battery is formed between the fillers, and the metal layer or the filler is corroded.

The shape of the filler containing a metal or a metal compound is not particularly limited, and examples thereof include a particulate form (including a spherical shape, an elliptical shape), a flat shape, a columnar shape, a needle shape (including a square shape, a dendritic shape), and an indefinite shape. . These shapes can be confirmed using a laser diffraction/scattering particle size distribution measuring apparatus or a scanning electron microscope (SEM).

As the filler containing a metal or a metal compound, it is preferred to use aluminum nitride powder, alumina powder, and needle-shaped (particularly tetrapotium) zinc oxide powder.

The thermal conductivity of zinc oxide is lower than that of aluminum nitride. However, when a tetragonal zinc oxide powder is used, a heat release member having superior heat release characteristics than the case of using particulate zinc oxide powder is obtained. Moreover, by using the tetragonally shaped zinc oxide powder, the occurrence of peeling between the layers of the metal layer and the graphite layer can be reduced due to the anchoring effect.

Moreover, aluminum oxide has a low thermal conductivity compared to aluminum nitride or zinc oxide, but is chemically stable and does not react or dissolve in water or acid due to water or acid, so that high weather resistance can be obtained. Exhaust component.

When aluminum nitride powder is used as the filler containing a metal or a metal compound, a heat releasing member having more excellent heat release characteristics can be obtained.

The average diameter of the primary particles of the filler containing a metal or a metal compound may be appropriately selected according to the size of the heat releasing member to be formed, the thickness of the subsequent layer, and the like, from the lamination direction of the bonding layer in the laminated body. From the viewpoint of thermal conductivity and the like, it is preferably 0.001 μm to 30 μm, more preferably 0.01 μm to 20 μm. Filler containing metal or metal compound The average diameter can be confirmed by a laser diffraction/scattering particle size distribution measuring apparatus or a scanning electron microscope (SEM).

In addition, the average diameter of the filler containing a metal or a metal compound means the diameter of the particle (the length of the long axis in the case of an ellipsoidal shape) when the filler is in the form of particles, and the filler is flat. In the case of the case, the longest side refers to the case where the filler is columnar, which means that the diameter of the circle (the long axis of the ellipse) or the length of the column is longer than one of the lengths of the column. The length of the pointer.

Examples of the filler containing the carbon material include graphite powder (natural graphite, artificial graphite, expanded graphite, Ketjen Black), carbon nanotubes, diamond powder, carbon fiber, fullerene, etc., and excellent self-conductivity. In view of the above, graphite powder, carbon nanotubes and diamond powder are preferred.

The average diameter of the primary particles of the filler containing carbon material may be appropriately selected according to the size of the heat releasing member to be formed, the thickness of the subsequent layer, and the like, from the direction of lamination of the laminate in the laminate. The thermal conductivity and the like are preferably 0.001 μm to 20 μm, more preferably 0.002 μm to 10 μm. The average diameter of the filler containing the carbon material can be confirmed using a laser diffraction/scattering particle size distribution measuring apparatus or a scanning electron microscope (SEM).

In addition, the average diameter of the carbon nanotube or carbon fiber refers to the length of the tube or fiber.

The thermally conductive filler may be directly used as a commercial product having an average diameter or shape within a desired range, or may be pulverized and classified using a commercially available product. Heating or the like is such that the average diameter or shape becomes a desired range.

Further, the average diameter or shape of the thermally conductive filler may vary during the manufacturing process of the heat releasing member of the present invention, but it is only necessary to formulate a filler having the average diameter or shape in the composition.

As the thermally conductive filler, a commercially available product subjected to a surface treatment such as a dispersion treatment or a water repellent treatment may be used as it is, or a surface treatment agent may be removed from the commercially available product. Further, it is also possible to use a surface treatment of a commercially available product which has not been subjected to surface treatment.

In particular, since aluminum nitride and magnesium oxide are easily deteriorated by moisture in the air, it is desirable to use a water-repellent treatment.

The above-mentioned filler may be used alone or in combination of two or more kinds.

The blending amount of the heat conductive filler is preferably 1 vol% to 80 vol%, more preferably 2 vol% to 40 vol%, still more preferably 2 vol% to 30 vol%, based on 100 vol% of the adhesive layer.

When the thermally conductive filler is contained in the amount in the adhesive layer, the adhesion is maintained, and the thermal conductivity of the subsequent layer is improved, which is preferable.

When the blending amount of the thermally conductive filler is less than or equal to the upper limit of the range, an adhesive layer having a high bonding strength to the metal layer or the graphite layer is obtained; and if the blending amount of the thermally conductive filler is at least the lower limit of the range, It is preferable to obtain an adhesive layer having high thermal conductivity.

[additive]

The additive is not particularly limited as long as the effects of the present invention are not impaired, and examples thereof include an antioxidant, a decane coupling agent, a thermosetting resin, and hardening. Agent, copper poison inhibitor, metal passivator, rust inhibitor, adhesive, anti-aging agent, defoamer, static preventive agent, weathering agent, etc.

For example, in the case where the resin forming the adhesive layer is deteriorated by contact with a metal, it is preferable to add a copper poison inhibitor or a metal passivating agent as exemplified in Japanese Laid-Open Patent Publication No. Hei 5-48265; The adhesion between the filler and the polyvinyl acetal resin is preferably a decane coupling agent.

As the decane coupling agent, a decane coupling agent (trade name: S330, S510, S520, S530) manufactured by JNC Co., Ltd. or the like is preferable.

The amount of the decane coupling agent added is preferably from 1 part by weight to 10 parts by weight per 100 parts by weight of the total amount of the resin contained in the adhesive layer, from the viewpoint of improving the adhesion between the adhesive layer and the metal layer. Parts by weight.

The polyethylene acetal resin constituting the adhesive layer has been used for enamelled wires and the like in the past, and is a resin which is difficult to be deteriorated by contact with metal or which is difficult to deteriorate the metal. However, in the case of using a heat releasing member in a high-temperature and high-humidity environment, Copper poison inhibitors or metal passivators can also be added. The copper poison inhibitor is preferably Mark ZS-27, Mark CDA-16 manufactured by AIDCO Co., Ltd.; SANKO-EPOCLEAN manufactured by Sanko Chemical Industry Co., Ltd.; Irganox MD1024 manufactured by BASF Corporation, etc. .

The amount of the copper poison inhibitor added is preferably 0.1 parts by weight with respect to 100 parts by weight of the total amount of the resin contained in the adhesive layer, from the viewpoint of preventing deterioration of the resin in the portion where the adhesive layer is in contact with the metal. ~3 parts by weight.

[solvent]

As the solvent, if the polyvinyl acetal resin is soluble, There is no particular limitation, and preferred are solvents for dispersing the thermally conductive filler, and examples thereof include methanol, ethanol, n-propanol, isopropanol, n-butanol, second butanol, n-octanol, diacetone alcohol, and benzyl alcohol. Alcohol solvent; cellosolve, ethyl 赛路苏, butyl 赛路苏, etc. Solvent solvent; acetone, methyl ethyl ketone, cyclohexanone, cyclopentanone, isophorone, etc. a ketone solvent; a guanamine solvent such as N,N-dimethylacetamide, N,N-dimethylformamide or 1-methyl-2-pyrrolidone; methyl acetate, ethyl acetate, etc. Ester solvent; ether solvent such as dioxane or tetrahydrofuran; chlorinated hydrocarbon solvent such as dichloromethane or chloroform; aromatic solvent such as toluene or pyridine; dimethyl hydrazine; acetic acid; terpineol; Kikabi alcohol; butyl carbitol acetate and the like.

These solvents may be used singly or in combination of two or more.

It is preferable that the resin concentration in the composition is from 3% by mass to 30% by mass, and more preferably from 5% by mass to 20% by mass, from the viewpoints of easiness of production and heat release characteristics of the heat releasing member. The solvent is used in an amount.

[The physical properties of the layer, etc.]

The thermal conductivity of the adhesive layer in the lamination direction of the laminate is preferably 0.05 W/m. K~50W/m. K, more preferably 0.1W/m. K~20W/m. K.

When the thermal conductivity of the adhesive layer is within the above range, a heat releasing member excellent in heat dissipation property and adhesion property can be obtained.

When the thermal conductivity of the adhesive layer is not more than the upper limit of the above range, the adhesion between the metal layer and the graphite layer is high, and a heat releasing member excellent in mechanical strength and durability is obtained, which is preferable. On the other hand, if the thermal conductivity of the bonding layer is When the temperature is higher than the lower limit of the range, a heat releasing member having excellent heat dissipation property is obtained, which is preferable.

The thermal conductivity of the adhesive layer in the lamination direction of the laminated body may be based on a thermal diffusivity obtained by a laser flash or Xenon flash thermal diffusivity measuring device, and differential scanning scanning device (differential scanning) Calorimeter, DSC) is calculated by the specific heat obtained, the density obtained by Archimedes' law, and the like.

The thickness of the adhesive layer is not particularly limited. If the thickness of the metal layer and the graphite layer is as close as possible, it is preferable to reduce the thermal resistance and the like, and it is preferable to have a thickness as thin as possible. It is 0.05 μm to 10 μm, and more preferably 0.1 μm to 7 μm.

Since the adhesive layer of the heat releasing member of the present invention is formed of a composition containing a polyvinyl acetal resin, the metal layer and the graphite layer can be bonded even if the thickness of the adhesive layer is 1 μm or less.

In addition, the thickness of the adhesive layer refers to a metal layer or a graphite layer that is in contact with one surface of the one-layer adhesive layer, and a metal that is in contact with the surface opposite to the surface of the metal layer or the graphite layer of the adhesive layer. The thickness between layers or graphite layers. Wherein, in the case of using the graphite layer as shown in FIG. 2 or FIG. 3, it also refers to the thickness between the metal layer and/or the graphite layer, and does not include the adhesive layer which can be filled by the hole or the slit portion of the graphite layer. The thickness.

Further, the thermally conductive filler which may be contained in the adhesive layer may be stuck to the graphite layer or the like, but even in this case, the thickness of the adhesive layer means a metal which does not consider the portion of the filler which is stuck into the graphite layer. The thickness between the layers and/or the graphite layers.

<metal layer>

The metal layer is a laminate for improving the heat capacity, mechanical strength, workability, and the like of the discharge member.

The metal layer is preferably a layer containing a metal having excellent thermal conductivity, and more preferably a layer comprising gold, silver, copper, aluminum, nickel, and an alloy containing at least any one of the metals, further preferably A layer comprising an alloy of silver, copper, aluminum, nickel, and at least any one of the metals is exemplified, and particularly preferably a layer comprising one metal selected from the group consisting of copper: Aluminum and an alloy containing at least any one of these metals.

The alloy may be in any state of a solid solution, a eutectic or an intermetallic compound.

Specific examples of the alloy include phosphor bronze, copper nickel, duralumin, and the like.

The thickness of the metal layer is not particularly limited, and may be appropriately selected in consideration of the use, weight, thermal conductivity, and the like of the resulting discharge member. Preferably, the thickness of the graphite layer is 0.01 to 100 times, more preferably 0.1 times to 10 times the thickness. When the thickness of the metal layer is within the above range, a heat releasing member excellent in heat release characteristics and mechanical strength can be obtained.

<graphite layer>

The graphite layer has a large thermal conductivity, is light and flexible. By using such a graphite layer, a heat releasing member excellent in heat release characteristics and lightweight can be obtained.

The graphite layer is not particularly limited as long as it is a layer containing graphite, and can be produced, for example, by the method described in JP-A-61-275117 and JP-A-11-21117. Can also make Use commercial products.

As a commercially available product, an artificial graphite sheet produced from a synthetic resin sheet can be exemplified by eGRAF SPREADERSHIELD SS-1500 (manufactured by GrafTECH International), GRAPHINITY (manufactured by Kaneka Co., Ltd.), and PGS graphite. The natural graphite sheet produced from natural graphite, such as a sheet (made by Panasonic Corporation), is eGRAF SPREADERSHIELD SS-500 (made by GrafTECH International).

The thermal conductivity of the graphite layer in a direction substantially perpendicular to the lamination direction of the laminate is preferably 250 W/m. K~2000W/m. K, more preferably 500W/m. K~2000W/m. K. By setting the thermal conductivity of the graphite layer to the above range, a heat releasing member excellent in heat dissipation property and heat absorption property can be obtained.

The thermal conductivity of the graphite layer in a direction substantially perpendicular to the lamination direction of the laminate may be determined by a laser rapid or 氙 rapid thermal diffusivity measuring device, DSC, and Archimedes' law, respectively, to determine thermal diffusivity, specific heat , density, determined by multiplying these.

The thickness of the graphite layer is not particularly limited, and a thick layer is preferable in order to obtain an exothermic member excellent in exothermic characteristics, more preferably 15 μm to 600 μm, still more preferably 15 μm to 500 μm, and particularly preferably 20 μm. ~300μm.

<Resin layer>

The heat releasing member of the present invention may have a resin layer on one or both sides of the outermost layer in order to resist oxidation or improve design.

The resin layer is not particularly limited as long as it is a layer containing a resin, and the tree Examples of the fat include an acrylic resin, an epoxy resin, an alkyd resin, an amine ester resin, and a nitrocellulose which are widely used as a coating material, and among these, a resin having heat resistance is preferable.

As a commercial item of the coating material containing the said resin, the heat resistant coating material (The heat-resistant paint of the OneITSUMO Co., Ltd. OneTouch) etc. are mentioned.

The resin layer may contain the thermally conductive filler or a filler having a high far-infrared emissivity in order to impart heat dissipation capability to the surface of the heat-releasing member due to far-infrared radiation.

The filler having a high far-infrared emissivity is not particularly limited. For example, it is preferably selected from the group consisting of minerals such as cordierite and mullite; nitrides such as boron nitride and aluminum nitride; cerium oxide and aluminum oxide; At least one filler of a group consisting of oxides such as zinc oxide and magnesium oxide; tantalum carbide; and graphite.

The kind of the resin used in the resin layer may be appropriately selected depending on the use temperature of the heat releasing member, the method or temperature at which the resin layer is formed.

Further, as the type of the filler used in the resin layer, a filler having a high thermal conductivity and/or a filler having a high far-infrared emissivity may be appropriately selected depending on the use of the heat-releasing member.

<Configuration of heat release member, etc.>

The heat-releasing member of the present invention is not particularly limited as long as it includes the laminate, and may be a laminate in which a plurality of metal layers and graphite layers are alternately laminated on the graphite layer of the laminate via the adhesive layer, or A laminate of a plurality of metal layers and/or graphite layers is laminated on the graphite layer of the laminate via the subsequent layers in an arbitrary order.

In the case where a plurality of metal layers, graphite layers or subsequent layers are used, the layers may be the same layer or different layers, and it is preferred to use the same layer. Moreover, the thickness of the layers may be the same or different.

The order of the lamination may be appropriately selected depending on the intended use, and specifically, it may be selected in consideration of desired heat release characteristics, design properties, corrosion resistance, and the like.

The number of the layers to be laminated may be appropriately selected depending on the intended use, and specifically, the size of the heat releasing member, the heat releasing property, and the like may be selected.

From the viewpoint of obtaining a heat releasing member excellent in mechanical strength and workability, etc., it is preferred that the outermost layer of the heat releasing member of the present invention is a metal layer.

Further, in the case of using the heat releasing member of the present invention in the aspect shown in Fig. 1, the layer farthest from the heat generating body 7 (the metal layer 6 in Fig. 1) may not be combined with the adhesive layer. The shape of the side to be joined is set to a shape having a large surface area, for example, a sword-like shape or a bellows shape, and the area of the opposite surface of the layer farthest from the heating element 7 in contact with the external layer is in contact with the outside air. Increase.

The heat radiating member of the present invention is preferably a laminated body 1 as shown in FIG. 1 in that it has a metal layer 2 and an adhesive layer sequentially stacked in order to provide excellent heat release characteristics, mechanical strength, light weight, and ease of manufacture. 3. Graphite layer 4, subsequent layer 5 and metal layer 6.

Further, in the case of manufacturing the heat releasing member including the laminated body 1 shown in Fig. 1, that is, in accordance with the intended use, in particular, the bonding strength of the metal layers (2 and 6) of the graphite layer 4 interposed therebetween is required. High layered body In the case of the shape, the layer 3 and the layer 5 can also be directly connected. As such an example, a method of using the graphite layer 4' provided with the hole 8 as shown in Fig. 2 or the graphite layer 4" having the slit 9 as shown in Fig. 3 can be cited.

The shape, the number, or the size of the hole or the slit may be appropriately selected in consideration of mechanical strength and heat release characteristics of the heat releasing member.

In the case of using a graphite layer provided with a hole or a slit, for example, a thicker layer is formed on the metal layer or the graphite layer than in the case where the hole or the slit is not provided, and the bonding is performed at a higher height. The temperature of the adhesive layer is such that the adhesive layer forming component flows into the hole or the slit during heating and pressure bonding, so that the adhesive layer forming component can be filled in the hole or the slit portion. Further, an adhesive layer of a portion of the metal layer that abuts on the slit or the hole of the graphite layer may be formed thickly by a dispenser or the like in advance.

Further, by using the graphite layer 4 which is smaller than the size of the metal layer 2 and the metal layer 6 (the longitudinal length and the lateral length of the layer), the adhesion layer 3 and the subsequent layer 5 are directly connected to each other, whereby a heat of high mechanical strength can be produced. member.

The resin layer may be formed directly on the metal layer or the graphite layer, or may be formed on the metal layer or the graphite layer via the adhesive layer.

Further, in the case where the heat releasing member of the present invention is in contact with the heat generating body, it is necessary to adhere the heat conductive grease or the heat conductive double-sided tape to the contact portion. Therefore, it is preferable that the resin layer is not present at the contact portion.

<Method of Manufacturing Heat Release Member>

The heat releasing member of the present invention can be produced by applying the composition to the metal plate forming the metal layer or the graphite plate forming the graphite layer, pre-drying as needed, and then using the metal plate and the graphite. Plate clamping the group It is arranged in such a way that it is heated while applying pressure. Further, in the production of the heat releasing member, it is preferable to apply the composition to both the metal plate and the graphite plate from the viewpoint of obtaining a heat releasing member having a high bonding strength between the metal layer and the graphite layer.

Before the coating of the composition, in view of obtaining a heat-dissipating member having a high strength of the metal layer and the graphite layer, the metal layer is preferably obtained by previously removing the oxide layer on the surface or degreasing the surface, and the graphite layer is preferably used. The surface is easily subjected to subsequent treatment by an oxygen plasma device or a strong acid treatment or the like.

The method of applying the composition to a metal plate or a graphite plate is not particularly limited, and a wet coating method in which the composition can be uniformly applied is preferably used. In the wet coating method, it is preferred to form a spin coating method in which a homogeneous film can be easily formed in the case of forming a thin film having an adhesive layer. In the case of importance in productivity, gravure coating, die coating, bar coating, reverse coating, roll coating, slit coating, spray coating, and conformal coating are preferred. Cloth method, reverse matching coating method, air knife coating method, curtain coating method, stick coating method, and the like.

The pre-drying is not particularly limited, and may be carried out by standing at room temperature for about 1 day to 7 days, preferably at a temperature of about 80 ° C to 120 ° C by a hot plate or a drying oven. Heat from 1 minute to 10 minutes.

Further, the pre-drying may be carried out in the atmosphere, but it may be carried out under an inert gas atmosphere such as nitrogen or a rare gas, or may be carried out under reduced pressure. Especially in the case of drying at a high temperature for a short period of time, it is preferred that It is carried out under an inert gas atmosphere.

The method of heating while applying pressure on one side is not particularly limited, and the pressure is preferably 0.1 MPa to 30 MPa, the heating temperature is preferably 200 ° C to 250 ° C, and the heating and pressing time is preferably 1 minute to 1 hour. . Further, the heating may be carried out in the atmosphere, or may be carried out under an inert gas atmosphere such as nitrogen or a rare gas, or may be carried out under reduced pressure. Particularly in the case of performing a short-time heating at a high temperature, it is preferably carried out under an inert gas atmosphere or under reduced pressure.

The heat releasing member having a resin layer on one side or both sides of the outermost layer may be manufactured by coating a resin layer on one side or both sides of the metal layer or the graphite layer of the outermost layer of the heat releasing member. The coating is allowed to dry as needed, after which the coating is allowed to harden. Further, it may be produced by previously forming a resin film, coating the composition on one side or both sides of the metal layer or the graphite layer of the outermost layer of the heat releasing member, and pre-drying as necessary. The resin film is brought into contact with the coated surface, and pressure, heating, or the like is applied as needed.

"Use of heat release components"

The heat-releasing member (laminate) of the present invention comprises an adhesive layer having a metal layer and a graphite layer which are excellent in strength and thin in thickness. Further, when the thermal conductive filler is contained in the adhesive layer, the thermal conductivity in a substantially vertical direction with respect to the lamination direction is high, and even if the overall thickness is thin, it has the same heat dissipation plate as the previous thick thickness or Its above exothermic properties. Further, the workability such as cutting, drilling, and demolding is excellent, and the adhesion between the metal layer and the graphite layer is strong and can be bent. Therefore, the heat releasing member of the present invention can be used in various applications. In particular, it can be suitably used in an electronic component or a battery.

Moreover, the heat releasing member of the present invention can also be suitably used as a heat equalizing plate for preventing color spots of a liquid crystal display or organic EL illumination.

As an example of use of the heat radiating member of the present invention in an electronic component or the like, as shown in FIG. 1 or FIG. 4, the heat radiating member (layered body) 1 of the present invention is brought into contact with the heat generating body 7 in the electronic component. Just use it for configuration.

1 is a schematic cross-sectional view showing an example of an electronic component in which a heat radiating member (layered body) 1 of the present invention is disposed substantially perpendicular to a surface of the heat generating body 7 in a lamination direction of the laminated body.

By disposing the heat radiating member 1 of the present invention as described above, heat can be diffused in a direction (lateral direction) substantially perpendicular to the laminating direction of the heat radiating member (laminate), and the temperature rise in the vicinity of the heat source can be alleviated.

In addition, FIG. 4 is a schematic cross-sectional view showing an example of an electronic component arranged such that the heat radiation member 1 shown in FIG. 1 is rotated by 90° and is in contact with the heat generating body 7.

By arranging the heat radiating member 1 of the present invention as described above, heat can be diffused in a direction (longitudinal direction) substantially perpendicular to the laminating direction of the heat radiating member (laminate), and the temperature rise in the vicinity of the heat source can be alleviated.

Further, when the heat releasing member of the present invention is disposed as shown in FIG. 4, a heat releasing member (layered body) may be cut in the laminating direction of the heat releasing member. When the heat radiating member of the present invention is disposed as shown in Fig. 4, the heat generated from the heat generating body 7 can be quickly released (e.g., moved to the cooling device), so that the temperature of the heat generating body 7 can be effectively suppressed. Rise.

<electronic components>

Examples of the electronic component include a central processing unit such as a wafer, a personal computer, a smart phone, or the like, which is used for image processing, an application specific integrated circuit (ASIC), and the like. , CPU), Light Emitting Diode (LED) lighting, etc.

[LED Lighting]

The LED illumination will be described with reference to FIG. 5. In addition, FIG. 5 is a schematic cross-sectional view showing an example of LED illumination in which the heat radiation member of the present invention is placed in contact with the back surface of the LED body with a heat transfer pad interposed therebetween. In particular, when an LED having a very large amount of heat such as an ultra-high brightness LED is used as the LED body, the use of the heat releasing member of the present application is effective. The LED illumination in FIG. 5 includes a heat radiation member 10, a thermal pad 11, an insulating film 12, an LED body 13, an electrode 14, and a metal wiring 15.

The LED body 13 that converts electric energy into light energy generates heat as it is turned on, and must be discharged outside the LED body 13. This heat is transmitted from the LED body 13 to the heat radiation member 10 of the present invention via the thermal pad 11, and heat is released by the heat radiation member 10.

[battery]

Examples of the battery include a lithium ion secondary battery, a lithium ion capacitor, a nickel hydrogen battery, and the like used in automobiles, mobile phones, and the like.

The lithium ion capacitor may also be a plurality of lithium ion capacitor unit series Or modules that are connected in parallel.

In this case, the heat releasing member of the present invention may be disposed in a manner of partially contacting the outer surface of the module as a whole or in a manner covering the entire module, or may be connected to a part of the outer surface of each lithium ion capacitor unit. The method is either configured to cover each unit.

[Example]

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 materials used in the examples of the present invention are as follows.

<Continuous layer resin>

. "PVF-C1": polyvinyl formal resin, manufactured by JNC Co., Ltd., Vinylec C (trade name)

. "PVF-C2": polyvinyl formal resin, manufactured by JNC Co., Ltd., Vinylec C (trade name)

. "PVF-K": polyvinyl formal resin, manufactured by JNC Co., Ltd., Vinylec K (trade name)

. "PVB": polyvinyl butyral, manufactured by Denki Chemical Industry Co., Ltd., Denka Butyral 3000-K (trade name)

. "Epoxy": Epoxy resin, manufactured by Mitsubishi Chemical Corporation, jER828 (trade name)

. "terpene-phenol": terpene-phenol resin, manufactured by YASUHARA CHEMICAL CO., LTD., YSPOLYSTER T160 (trade name)

. "Acrylic": acrylic adhesive, emerging plastics limited Made by the company, Acryl Dine B (trade name)

The structure and physical properties of "PVF-C1", "PVF-C2" and "PVF-K" described in Table 1 below are described.

<solvent>

. 1-methyl-2-pyrrolidone: manufactured by Wako Pure Chemical Industries Co., Ltd.

. Cyclopentanone: Wako Pure Chemical Industries Co., Ltd.

<thermally conductive filler>

. Zinc oxide powder: manufactured by AMTEC Co., Ltd., Pana-Tetra WZ-0511 (trade name, square shape, average diameter (length of needle): about 10 μm)

. Aluminum nitride powder: manufactured by Tokuyama Chemical Co., Ltd., aluminum nitride grade H (trade name, particle shape, average diameter (Al): 1 μm)

. Alumina powder: manufactured by Showa Denko Co., Ltd., alumina (low sodium) AL-47-H (trade name, particle shape, average diameter: 2.1 μm)

. Nano diamond powder: manufactured by CARBODEON, BLEND NUEVO (trade name, particle shape, average diameter: 0.004~0.006μm)

. Aluminum powder: manufactured by The Nilaco Corporation, aluminum powder (particulate, average diameter: 30 μm)

<graphite sheet>

. Graphite sheet (artificial graphite): manufactured by GrafTECH International, SS-1500 (trade name), thickness 25 μm, (thermal conductivity in the direction of the sheet: 1500 W/m.K)

. Graphite sheet (artificial graphite): manufactured by GrafTECH International, SS-1500 (trade name), thickness 40 μm, (thermal conductivity in the direction of the sheet surface: 1500 W/m.K)

. Graphite flakes (natural graphite): manufactured by GrafTECH International, SS-500 (trade name), thickness 76 μm, (thermal conductivity in the direction of the sheet: 500 W/m.K)

. Graphite sheet (artificial graphite) with acrylic adhesive: manufactured by Kaneka Co., Ltd., Japan, with a layer containing an acrylic adhesive (thickness: 12 μm) on one side of GRAPHINITY (thickness 25 μm) Thin slice

. Graphite sheet (artificial graphite) with an anthrone-based adhesive: a sheet made of a layer containing an anthrone-based adhesive (thickness: 40 μm) manufactured on one side of GRAPHINITY (thickness: 25 μm) manufactured by Kaneka Co., Ltd.

. PGS graphite flakes: manufactured by Matsushita Co., Ltd. EYG-S091203, thickness 25μm, (thermal conductivity in the direction of the sheet: 1600W/m.K)

<metal plate>

. Copper plate: manufactured by The Nilaco Corporation with a thickness of 0.1mm

. Copper plate: manufactured by The Nilaco Corporation with a thickness of 0.2mm

. Copper plate: manufactured by The Nilaco Corporation, thickness 0.4mm

. Copper foil: manufactured by The Nilaco Corporation with a thickness of 0.03mm

. Copper foil: manufactured by The Nilaco Corporation, thickness 0.05mm

. Electrolytic copper foil for printed circuit boards: manufactured by Mitsui Mining & Metal Co., Ltd., thickness 0.012mm

. Electrolytic copper foil for printed circuit boards: manufactured by Foton Metal Foil Powder Industry Co., Ltd., thickness 0.019mm

. Silver foil: Made by The Nilaco Corporation, thickness 0.03mm

. Aluminum plate: aluminum plate, manufactured by The Nilaco Corporation, thickness 0.1mm

. Aluminum foil: manufactured by The Nilaco Corporation with a thickness of 0.03mm

. Aluminum foil: manufactured by Donghai Aluminum Foil Co., Ltd., thickness 0.02mm

. Copper-nickel alloy (white copper) foil: manufactured by The Nilaco Corporation, Thickness is 0.03mm

. Phosphor bronze foil: manufactured by The Nilaco Corporation, thickness 0.03mm

<Resin for Resin Layer>

. "Heat-resistant coating": OneTouch (trade name) manufactured by Austin Motor Co., Ltd.

. "Epoxy": Epoxy resin, manufactured by Mitsubishi Chemical Corporation, jER828 (trade name)

. "clear lacquer": Clear spray paint, manufactured by Kansai Paint Co., Ltd., SELVA 26 (trade name)

. "PMMA": Methyl methacrylate polymer, manufactured by Sanyu Research Institute Co., Ltd., MA-830-M50 (trade name)

<Refiller for Resin Layer>

. Cordierite powder: Marsui Glaze Co., Ltd. (Marusu Glaze Co., Ltd.) manufactured and synthesized cordierite SS-1000 (average particle size 1.7 μm)

. Alumina powder: manufactured by Showa Denko Co., Ltd., alumina (low sodium) AL-47-H (trade name, particle shape, average diameter: 2.1 μm)

. Tantalum carbide powder: 碳-Aldrich Japan K.K., manufactured by Sigma-Aldrich Japan K.K., 200 mesh to 450 mesh

. Magnesium oxide powder: Magnesium oxide, manufactured by Kanto Chemical Co., Ltd., Rotter

<Evaluation of thermal conductivity>

The thermal diffusivity and thermal conductivity of the obtained heat releasing member in the direction perpendicular to the plate surface (the lamination direction of the laminated body) were determined as follows. The heat-releasing members obtained in the following Examples 1 to 13 and Comparative Examples 1 to 3 were cut out into square plates of about 9.8 mm, and carbon spray (DGF manufactured by Nippon Ship Tools Co., Ltd.) was used. After coating on both sides, it was placed on a sample holder of the LFA-447 type rapid thermal diffusivity measuring device manufactured by NETZSCH. After the sample holder is at 25 ° C, the heat-dissipating member is placed at a predetermined strength with a xenon lamp. The irradiation was measured for the temporal change in the heat radiation intensity from the surface of the heat-releasing member opposite to the lamp irradiation surface, and analyzed by the attached software to obtain the thermal diffusivity. The measurement conditions such as the gain of the detector were set to be automatic, and for analysis, in order to evaluate the comprehensive thermal properties of the heat radiation member, a single-layer plate was used for calculation.

In addition, the specific heat of the heat releasing member (measured by a Diamond DSC type input compensation type differential scanning calorimeter manufactured by PerkinElmer Co., Ltd.) and specific gravity were obtained (by Alfa Mirage Co., Ltd. (Alfa) The measurement was carried out by an MD-300s type electronic hydrometer manufactured by Mirage Co., Ltd.), and the thermal conductivity was determined by a thermal conductivity = thermal diffusivity × specific heat x specific gravity. The thermal diffusivity and thermal conductivity of the heat-releasing members obtained in the following Examples 1 to 13 and Comparative Examples 1 to 3 are shown in Table 2.

In the case of a laminated heat releasing member, the heat conduction in a direction substantially perpendicular to the lamination direction of the laminated body is governed by the ratio of the layer having a high thermal conductivity, and thus is not greatly affected by the manufacturing method of the heat releasing member, and is basically Get the performance as shown in the design. Conversely, the reduction in the thermal resistance of the lamination direction of the laminate in the interface of the respective layers largely depends on the thermal resistance of the interface between the layers and the thermal resistance of the subsequent layer, and is preferably reduced. That is, the higher the thermal conductivity of the laminated body in the lamination direction, the more the metal layer and the graphite layer can be well followed, that is, the high-performance heat releasing member.

<Evaluation of exothermic characteristics>

On one side of the heat-releasing member obtained in the following Examples 14 to 37, a heat-resistant paint was sprayed in such a manner that the thickness of the coating film became about 20 μm (Oss) The heat-resistant paint OneTouch manufactured by Mocha Co., Ltd. makes it dry. Using a double-sided tape (thermal conductive adhesive transfer tape No. 9885 manufactured by Sumitomo 3M Co., Ltd.), the side of the heat-dissipating member which is not coated with the heat-resistant paint and the T0220-packaged transistor (manufactured by Toshiba Co., Ltd.) 2SD2013) fit. K thermocouple (ST-50 manufactured by Physicochemical Co., Ltd.) is attached to the back surface of the transistor to which the surface of the heat releasing member is attached, and a temperature data recorder (GL220 manufactured by GRAPHTEC Co., Ltd.) is available. The personal computer records the temperature at which the transistor is attached to the opposite side of the surface of the heat releasing member. The crystal cell to which the thermocouple was mounted was placed in the center of a thermostatic chamber set at 40 ° C, and after confirming that the temperature of the transistor was 40 ° C and fixed, 1.0 V was applied to the transistor using a DC stabilized power source, and the surface temperature was measured. Variety. The temperature of the transistor after 1000 seconds of application or after 3000 seconds was measured. The results are shown in Table 3 or Table 4.

The transistor generates a fixed amount of heat if the same wattage is applied, so that the higher the heat release effect of the heat-dissipating member to be mounted, the lower the temperature. That is, the lower the temperature of the transistor, the more the heat releasing effect of the heat releasing member is high.

Further, as Comparative Examples 9 to 11, a copper plate having a thickness of 0.2 mm, 0.4 mm, and 0.05 mm was used instead of the heat radiation member, and the electric power was measured in the same manner for 1,000 seconds and after 3000 seconds. The temperature of the crystal. The results are shown in Table 3.

<Evaluation of adhesion>

The bonding strength between the metal layer and the graphite layer of the heat releasing member obtained in Examples 1 to 25 and Comparative Examples 1 to 8 was difficult to be peeled off due to the fact that the graphite layer had the property of splitting (in-layer peeling). Stretch The load is equal to the value obtained. Therefore, the metal portion of the heat releasing member produced in the example was peeled off, and the state of the inner surface of the metal layer was visually observed and evaluated. When the entire surface of the peeled metal layer was covered with the cleaved graphite, it was evaluated as ◎, and when only a small metal layer or the subsequent layer was exposed, it was evaluated as ○, and when the metal layer or the subsequent layer was exposed at 1/4 or more, the evaluation was performed. When it is Δ, it is evaluated as × when there is almost no graphite residue. The results are shown in Table 2 or Table 3.

[Example 1]

80 g of 1-methyl-2-pyrrolidone (NMP) was placed in a 200 ml three-necked flask, and a stirring blade made of a fluororesin was placed from the upper portion, and the stirring blade was rotated by a motor. Adjust the speed according to the viscosity of the solution. 10 g of polyvinyl formal resin (PVF-C1) was placed in the flask using a glass funnel. After rinsing the PVF-C1 attached to the funnel with 20 g of NMP, the funnel was taken out and covered with a glass lid. The obtained solution was heated while stirring in a water bath set to 80 ° C for 4 hours to completely dissolve PVF-C1 in NMP. After the stirred flask was taken out from the water bath and returned to room temperature, 10 g of zinc oxide powder was added as a thermally conductive filler using a dry funnel, and the mixture was stirred overnight to obtain an adhesive (composition).

The adhesive was applied at a size of 50 mm × 50 mm at a thickness of 1500 rpm using a spin coater (Model 1H-D3 manufactured by Mikasa Co., Ltd.) so that the thickness of the obtained adhesive layer became 4 μm. After being a 0.1 mm copper plate, it was pre-dried at 80 ° C for 3 minutes on a hot plate set at 80 ° C to obtain a copper plate with a coating film attached thereto. In addition, when the adhesive is applied to the copper plate, it is precipitated without coating the bottom of the flask. Coating was carried out by collecting the adhesive as a large secondary particle.

Two copper sheets with a coating film attached thereto were used, and the graphite film (SS-1500) having a thickness of 25 μm which was previously cut into 50 mm × 50 mm was placed on the inside of the coating film, and placed in a small heating press ( The hot plate of IMC-19EC small heating manual press manufactured by Imoto Manufacturing Co., Ltd.). At the same time, the two copper plates and the graphite flakes were not deviated, and the pressurization and depressurization were repeated several times, whereby the subsequent coating film was degassed, and then pressurized to 6 MPa. Thereafter, the hot plate was heated to 220 ° C by a heater to maintain the temperature and pressure for 30 minutes. After 30 minutes, the heater was turned off while maintaining pressure, and naturally cooled to about 50 °C. After cooling, the pressure is released to obtain a heat releasing member. Further, the thickness of the entire heat releasing member was reduced by 1/2 of the thickness of the two metal plates and the thickness of the graphite sheet as the thickness of the adhesive layer. The thickness of the heat releasing member was measured by a digital gauge ID-C112CXB manufactured by Mitutoyo Corporation.

[Comparative Example 1]

In the same manner as in Example 1, except that a copper plate to which a thermal conductive adhesive transfer tape No. 9882 (thickness: 50 μm) was attached, which was manufactured by Sumitomo 3M Co., Ltd., was used instead of the copper plate with the coating film attached thereto. The heat release member is obtained by performing the ground.

[Example 2 to Example 11, Example 13 to Example 15, Example 17 to Example 24, and Comparative Example 4 to Comparative Example 8]

In Example 1, as shown in Tables 2 to 3, the type and thickness of the metal plate and the graphite sheet were changed, and the type of the resin and the type of the thermal conductive filler (whether or not) were changed as shown in Tables 2 to 3 or Adhesive of content, The heat release member was obtained in the same manner as in Example 1 except that the thickness of the adhesive layer was changed as shown in Tables 2 to 3.

In the following table, the thickness of the heat releasing member measured by the digital gauge ID-C112CXB manufactured by Mitutoyo Co., Ltd. minus the thickness of the two metal sheets and the thickness of the graphite sheet is less than 1 The case is described as the measurement limit or less.

Further, in the heat-releasing member obtained in Example 9, the cross section of the heat-releasing member was observed by a scanning electron microscope, and as a result, the thickness of the adhesive layer was varied depending on the position, and was about 0.3 μm to 0.5 μm.

[Example 12]

In Example 1, an adhesive having the type and content of the thermally conductive filler was changed as shown in Table 2, and the thickness of the adhesive layer was 1 μm in the same manner as in Example 1 to a size of 50 mm × 50 mm. A copper plate with a coating film was obtained by the same method as in Example 1 on a copper plate having a thickness of 0.2 mm.

The copper plate with the coating film attached thereto was placed in contact with a graphite sheet (SS-1500) having a thickness of 25 μm, and placed in a small heat press (IMC-19EC type small manufactured by Imoto Seisakusho Co., Ltd.). Heat the manual press on the hot plate. At the same time, the copper plate and the graphite sheet were not deviated, and the pressurization and depressurization were repeated several times, whereby the subsequent coating film was degassed, then pressurized, and kept at room temperature and 6 MPa for 120 minutes. Exhaust component.

Further, the thickness of the subsequent layer is a value obtained by subtracting the thickness of the metal plate from the thickness of the graphite sheet as a whole of the heat releasing member. With Mitutoyo shares The thickness of the heat releasing member was measured by a digital gauge ID-C112CXB manufactured by the company.

[Comparative Example 2 and Comparative Example 3]

In Example 12, a graphite sheet with an acrylic adhesive or a graphite sheet with an anthrone-based adhesive was used instead of the adhesive and graphite sheet (SS-1500), and the copper sheets described in Table 2 were used. The heat-releasing member was obtained in the same manner as in Example 12 except that the adhesive sheets of the graphite sheets to which the adhesives were attached were placed in contact with each other. Further, the thickness of the adhesive layer was measured in the same manner as in Example 12.

[Example 16]

In the same manner as in Example 1, except that the content of the thermally conductive filler was changed as shown in Table 3, the adhesive was prepared.

The adhesive was applied to one surface of a graphite sheet (SS-1500) having a thickness of 25 μm so that the thickness of the adhesive layer was 1 μm, and coating was carried out in the same manner as in Example 1 except that the adhesive was applied. Drying, thereby obtaining a graphite sheet with a subsequent coating film.

The graphite sheet with the coating film attached thereto was placed in contact with a graphite sheet (SS-1500) having a thickness of 25 μm, and placed in a small heat press (IMC-19EC type manufactured by Imoto Seisakusho Co., Ltd.). Small heating manual press) on the hot plate. At the same time, the two graphite sheets were pressed and decompressed several times, and the subsequent coating film was degassed, and then pressurized, and kept at room temperature and 6 MPa for 120 minutes. A laminate having two graphite sheets laminated thereon was obtained.

In Example 1, the resulting laminate was used instead of graphite flakes, except The heat radiation member was obtained in the same manner as in Example 1. That is, a heat releasing member having a structure of a copper plate / an adhesive layer / a graphite sheet / an adhesive layer / a graphite sheet / an adhesive layer / a copper plate is obtained.

Further, 1/3 of the value obtained by subtracting the thickness of the two copper plates from the thickness of the entire two heat-dissipating members and the thickness of the two graphite sheets is the thickness of the adhesive layer. The thickness of the heat releasing member was measured by a digital gauge ID-C112CXB manufactured by Mitutoyo Corporation.

[Example 25]

In the same manner as in Example 1, except that the content of the thermally conductive filler was changed as shown in Table 3, an adhesive was obtained.

The adhesive was applied to an aluminum foil having a size of 50 mm × 50 mm and a thickness of 0.03 mm by the same method as in Example 1 so that the thickness of the obtained adhesive layer became 1 μm, and the thickness of the obtained adhesive layer was obtained. In the form of 1 μm, the adhesive was applied onto a copper foil having a size of 50 mm × 50 mm and a thickness of 0.03 mm, and pre-dried to obtain an aluminum foil with a subsequent coating film and copper with a subsequent coating film. Foil.

The aluminum foil and the copper foil with the coating film were placed thereon, and the graphite film (SS-1500) having a thickness of 25 μm which was previously cut into 50 mm × 50 mm was sandwiched by the subsequent coating film, and the same as in Example 1. In the method, it is noted that the aluminum foil, the copper foil, and the graphite sheet are not deviated, and one side is obtained to obtain a heat releasing member.

In addition, in the evaluation of the heat release property, the heat-resistant paint (heat-resistant paint OneTouch manufactured by Osmo Corporation) was sprayed on the aluminum foil so that the thickness of the coating film became about 20 μm, and dried. In addition to using this The exothermic characteristics were evaluated in the same manner as described above except for the heat releasing member.

[Example 26]

An adhesive was obtained in the same manner as in Example 1 except that the thermal conductive filler was not used and the cyclopentanone was used instead of NMP. A heat releasing member was obtained in the same manner as in Example 1 except that the type of the metal layer and the thickness of the adhesive layer were changed as shown in Table 4, using the obtained adhesive.

Further, after the case of Example 26, the heat-resistant paint was not applied at the time of evaluation of the heat release characteristics.

[Example 27]

A laminate was obtained in the same manner as in Example 1 except that the type of the metal plate and the thickness of the adhesive layer were changed as shown in Table 4, as shown in Table 4.

On one side of the obtained laminated body, a heat-resistant coating (heat-resistant paint OneTouch manufactured by Osmo Corporation) was sprayed so as to have a thickness of the coating film of about 30 μm, and dried to obtain a laminate. a heat releasing member of the resin layer. Using a double-sided tape (thermal conductive adhesive transfer tape No. 9885 manufactured by Sumitomo 3M Co., Ltd.), the surface of the heat releasing member on the opposite side to the surface of the resin layer (metal layer) and the T0220 packaged transistor (Toshiba) In addition to the above-mentioned "evaluation of the heat release characteristics", the heat release characteristics were evaluated in the same manner as in the above-mentioned "2SD2013" manufactured by the company.

[Example 28]

The laminate was obtained in the same manner as in Example 27.

Epoxy resin (jER828) 10g dissolved in 90g of NMP In the solution, 10% by weight of cordierite based on the resin component was added, and a defoaming mixer ARE-250 manufactured by Shinky Co., Ltd. was used, and the mixture was stirred at 2000 rpm for 5 minutes, and then 2000 rpm. The rotation speed was subjected to defoaming for 5 minutes, whereby an exothermic paint was obtained. Using a spin coater (Model 1H-D3 manufactured by Mikasa Co., Ltd.), the coating material was applied to one of the copper foils of the laminate so that the thickness of the obtained resin layer was 0.03 mm, and then set. The heating plate was heated at 120 ° C for 30 minutes, whereby a heat releasing member having a resin layer formed on the laminated body was obtained.

Further, the thickness of the resin layer is adjusted by adjusting the resin concentration in the coating and the rotation speed of the spin coater.

[Example 29 to Example 36]

The laminate was obtained in the same manner as in Example 27.

A heat-releasing member having a resin layer formed on the laminated body was obtained in the same manner as in the above-described 28, except that the type of the resin to be formed into the resin layer and the type of the filler were changed as shown in Table 4.

[Example 37]

A laminate was obtained in the same manner as in Example 1 except that the type of the metal plate and the graphite sheet and the thickness of the subsequent layer were changed as shown in Table 4, as shown in Table 4.

The heat-releasing member in which the resin layer was formed on the laminated body was obtained in the same manner as in the above-described 28, except that the type of the resin forming the resin layer and the type of the filler were changed as shown in Table 4.

[Research on Thermally Conductive Filler]

Comparing the thermal diffusivity and the thermal conductivity of the exothermic members of Examples 1 to 5, it can be seen that, in comparison with the exothermic member of Example 2 in which the thermally conductive filler is not disposed in the subsequent layer, heat conduction is provided in the adhesive layer. The heat transfer member of the filler has a higher thermal conductivity.

Compared with aluminum nitride, the thermal conductivity of zinc oxide is less than one digit, but if Example 1 is compared with Example 3, the situation of zinc oxide in the subsequent layer and the case of formulating aluminum nitride are obtained. There is no significant difference in the thermal conductivity of the heat releasing member. Moreover, the thickness of the subsequent layer is thinner than the length of the acicular portion of zinc oxide. The reason for this is that a portion of the needle extending in the direction of lamination of the heat releasing member (laminate) in the needle crystal of zinc oxide is stuck into the graphite layer, and this portion efficiently transfers heat from the metal layer to the graphite layer.

Even if the amount of nano-diamond is small, it exhibits the same exothermic performance as in the case of using other fillers. The reason is considered to be that the thermal conductivity of diamond is very high compared to other thermally conductive fillers. The production of nanodiamonds is small, but can be used especially in the case of producing a high-performance heat release plate in a small amount.

[Study on the amount of thermal conductive filler added]

Comparing Example 1 with Examples 6 to 8, it can be seen that the higher the amount of the thermally conductive filler, the higher the thermal conductivity. However, if too much filler is added, there exists a tendency for the adhesive strength with a metal layer and a graphite layer to fall, and it is desirable to balance the thermal conductivity and the adhesive strength.

[Research on the type of resin]

If Example 1 is compared with Comparative Example 1, the result obtained in Example 1 The heat radiating member has a higher thermal conductivity in the lamination direction of the heat releasing member (layered body) than the heat releasing member which is laminated using a commercially available thermally conductive adhesive transfer tape.

Further, as for the heat releasing members obtained in Example 12, Comparative Example 2, and Comparative Example 3, any of the heat releasing members had a bonding strength higher than that of the graphite layer. In the case where a polyvinyl acetal resin is used as the type of the resin of the adhesive layer, the bonding strength can be maintained even if the thickness of the adhesive layer is reduced, so that the heat conductivity of the obtained heat releasing member (laminate) in the lamination direction is in the case of using polyethylene. The acetal resin is the highest in the case of the type of the resin of the adhesive layer. Therefore, it is understood that by using a polyvinyl acetal resin, a heat-releasing member having high performance as compared with the case of using a commercially available adhesive can be produced.

Comparing Example 2, Example 9 to Example 11, and Comparative Example 4 to Comparative Example 8, it was found that when a polyvinyl acetal resin was used as the type of the resin of the adhesive layer, the obtained heat releasing member exhibited good adhesion.

The polyethylene acetal resin is excellent in adhesion to the metal layer and the graphite layer, so that the adhesive layer can be thinned. In particular, it is understood that the thermal conductivity of the heat releasing member is drastically increased even in the case where a thinner back layer is formed using PVF-C2 (Example 9).

Further, when an acrylic adhesive or an epoxy resin is used as the adhesive layer forming material, if the thickness of the adhesive layer is 1 μm, the metal layer and the graphite layer cannot be completely adhered to.

Further, as shown in Example 25, in the case where the heat releasing member of the present invention contains two or more metal layers, different metal layers may be used as needed. Such a heat releasing member can also use, for example, a copper layer having a good thermal conductivity due to the surface in contact with the heater, and an aluminum layer which is difficult to rust on the opposite side. A heat releasing member that combines heat release characteristics with difficulty in rusting is obtained. The exothermic characteristics of the heat releasing member showed an intermediate property of using only the copper foil as the heat releasing member of the metal sheet (Example 19) and the exothermic property of using only the aluminum foil as the heat releasing member of the metal sheet (Example 20).

[Study on metal layers]

In Table 2, when Example 15 was compared with Comparative Example 9, it was found that even in the case where the thermal conductive filler was not disposed in the adhesive layer, the copper plate having a thickness of 0.2 mm which is substantially the same thickness as the heat releasing member was exothermic. Sex is also good. Further, when Example 14 was compared with Comparative Example 10, it was found that the resulting exotherm was obtained by blending a thermally conductive filler in the adhesive layer with a 0.4 mm thick copper plate having a thickness twice the thickness of the heat releasing member. The heat release performance of the member becomes good. Therefore, it is understood that by using the heat releasing member of the present invention, a high-performance heat releasing member having the same or higher heat releasing performance and having a weight and a thickness of half of copper can be obtained.

[Research on resin layer]

The heat releasing member of the present invention can be provided with a filler having a high thermal conductivity similar to that of the user in the adhesive layer, a filler having a high far-infrared emissivity such as cordierite, mullite, or cerium oxide, or the like. The exothermic resin layer on both sides of the filler further enables the heat release capability.

In Table 4, it is understood that the heat releasing member containing the resin layer can further lower the temperature of the crystal cell, that is, the heat releasing ability, as compared with the heat releasing member not containing the resin layer. Further, it is understood that the heat releasing capability of the heat releasing member containing the resin layer containing the filler such as cordierite, alumina, tantalum carbide or magnesium is further improved as compared with the heat releasing member containing the resin layer formed of the heat resistant coating material.

1‧‧‧heat release member (layered body)

2, 6‧‧‧ metal layer

3, 5‧‧‧Next layer

4, 4', 4" ‧ ‧ graphite layer

7‧‧‧heating body

8‧‧‧ hole

9‧‧‧Slit

10‧‧‧Exhaust components

11‧‧‧ Thermal pad

12‧‧‧Insulation film

13‧‧‧LED body

14‧‧‧Electrode

15‧‧‧Metal wiring

Fig. 1 is a schematic cross-sectional view showing an example of an electronic component including a heat releasing member of the present invention.

Fig. 2 is a schematic view showing an example of a graphite layer provided with a hole.

3 is a schematic view showing an example of a graphite layer provided with a slit.

Fig. 4 is a schematic cross-sectional view showing an example of an electronic component including the heat radiation member of the present invention.

Fig. 5 is a schematic cross-sectional view showing an example of LED illumination including the heat radiation member of the present invention.

1‧‧‧heat release member (layered body)

2, 6‧‧‧ metal layer

3, 5‧‧‧Next layer

4‧‧‧ graphite layer

7‧‧‧heating body

Claims (25)

A heat releasing member comprising a laminate in which a metal layer and a graphite sheet are laminated via an adhesive layer, the adhesive layer being formed of a composition comprising a polyvinyl acetal resin, wherein the adhesive layer does not contain an epoxy resin. The heat release member according to claim 1, wherein the composition further comprises a thermally conductive filler. The heat release member according to claim 1, wherein the polyvinyl acetal resin comprises the following structural unit A, structural unit B, and structural unit C, (In structural unit A, R is independently hydrogen or alkyl) The heat release member according to claim 3, wherein the polyvinyl acetal resin further comprises the following structural unit D, (In Structural Unit D, R ^{1 is} independently hydrogen or an alkyl group having 1 to 5 carbon atoms). The heat release member according to claim 3, wherein R in the structural unit A is hydrogen or an alkyl group having 1 to 3 carbon atoms. The heat release member according to claim 4, wherein R in the structural unit A is hydrogen or an alkyl group having 1 to 3 carbon atoms. The heat radiating member according to claim 1, wherein the laminated layer has a thermal conductivity of 0.05 W/m in a lamination direction. K~50W/m. K. The heat release member according to claim 1, wherein the adhesive layer has a thickness of 0.05 μm to 10 μm. The heat release member according to claim 2, wherein The adhesive layer contains 1 vol% to 80 vol% of a thermally conductive filler with respect to 100 vol% of the adhesive layer. The heat release member according to claim 2, wherein the heat conductive filler comprises at least one powder selected from the group consisting of metal powder, metal oxide powder, metal nitride powder, and metal carbide powder. body. The heat radiating member according to claim 10, wherein the heat conductive filler comprises a material selected from the group consisting of aluminum nitride powder, aluminum oxide powder, zinc oxide powder, magnesium oxide powder, tantalum carbide powder, tungsten carbide powder, and aluminum powder. And at least one powder of the group consisting of copper powder. The heat release member according to claim 10, wherein the heat conductive filler has an average diameter of 0.001 μm to 30 μm. The heat release member according to claim 2, wherein the heat conductive filler is a filler containing a carbon material. The heat radiating member according to claim 13, wherein the heat conductive filler comprises at least one powder selected from the group consisting of graphite powder, carbon nanotubes, and diamond powder. The heat release member according to claim 1, wherein the graphite sheet has a thermal conductivity of substantially 250 W/m with respect to a lamination direction of the laminate. K~2000W/m. K. The heat releasing member according to claim 1, wherein the graphite sheet has a thickness of 15 μm to 600 μm. The heat releasing member according to claim 1, wherein the thickness of the metal layer is 0.01 to 100 times the thickness of the graphite sheet. The heat radiating member according to claim 1, wherein the metal layer is at least 1 group consisting of an alloy of silver, copper, aluminum, nickel, and at least one metal containing the metal. a layer of metal. The heat radiating member according to claim 1, wherein the metal layer is a layer of at least one metal comprising a group of copper, aluminum, and an alloy of at least one of the metals containing the metals. . The heat releasing member according to claim 1, wherein the heat releasing member comprises at least two metal layers, and the metal layer comprises an alloy of copper, aluminum, and at least any one of the metals. One or more metals of the group, at least two of which are different layers. The heat releasing member according to claim 1, wherein the outermost layer of the heat releasing member has a resin layer on one side or both sides. The heat releasing member according to claim 21, wherein the resin layer contains a filler containing an inorganic compound. The heat releasing member according to claim 21, wherein the resin layer comprises at least one selected from the group consisting of an acrylic resin, an epoxy resin, an alkyd resin, an amine ester resin, and a nitrocellulose. A resin and at least one compound selected from the group consisting of alumina, ceria, cordierite, mullite, tantalum carbide, and magnesium oxide. An electronic component comprising the heat release member according to claim 1 of the patent application. A battery comprising the invention as recited in claim 1 Exhaust component.