JP2018119063A - Resin composition and sheet comprising resin composition - Google Patents

Abstract

[PROBLEMS] To provide a resin composition having high thermal conductivity, flame retardancy and vibration absorption, flexible, high thickness accuracy, stable raw material supply capability during sheet production, and excellent sheet productivity. A sheet made of the resin composition is obtained. (A) 2-20% by mass of a copolymer containing a conjugated diene unit and a vinyl aromatic compound unit and / or a hydrogenated product thereof, (B) 2-20% by mass of a rubber softener, C) Thermally conductive filler 70 to 95% by mass, and (D) at least one additive selected from the group consisting of silica, talc, calcium carbonate, barium sulfate, kaolinite, apatite, diatomaceous earth, zeolite, and mica. The resin composition containing 0.1-3 mass%. [Selection] Figure 1

Description

  The present invention relates to a resin composition and a sheet comprising the resin composition.

Conventionally, heat transfer materials, adhesives, sealing materials, etc. with high heat transfer efficiency are used to cool or dissipate heat sources in various fields including the vehicle field, home appliance field, electric / electronic field, communication field, etc. Is needed.
In recent years, lithium-ion batteries have been used in the vehicle field, and lithium-ion batteries with higher capacity and output have been developed for the purpose of extending the mileage per unit charge and increasing the output. It has come to be installed in vehicles. As a result, the size of the lithium ion battery is increased, and accordingly, the temperature rise in the lithium ion battery cell is further increased.
In order to prevent this, a heat transfer material having a higher heat dissipation effect and a higher cooling effect has been demanded, including a system equipped with lithium ion battery cells.

Conventionally, a resin composition in which a heat conductive filler is added to and dispersed in a resin material has been used as a heat dissipation member.
For example, a resin composition in which a heat conductive filler is blended with a silicone resin is used.
In addition, a thermally conductive resin composition using a thermoplastic elastomer is also used.
For example, Patent Document 1 discloses a heat conductive elastomer composition in which a heat conductive filler made of aluminum hydroxide or the like is blended with an elastomer composition mainly composed of a styrene elastomer as a base material. The same document also discloses a resin composition containing aluminum hydroxide having two different average particle sizes.

Japanese Patent No. 5722284

The heat radiating member is required to be excellent in various physical properties depending on the application.
However, the conventionally proposed materials have a problem that sufficient physical properties are not yet obtained as a heat radiating member, and there is also a problem that there is room for improvement in terms of productivity. ing.
For example, in a vehicle application, in addition to a heat dissipation effect and a cooling effect, high reliability for ensuring safety is required. In particular, in the case of an electric vehicle using a lithium ion battery, there are many parts that operate at a high voltage, and further, the electrolyte easily ignites when exposed to air. It is important that it is difficult to do. For this reason, excellent flame retardancy is also required in electric vehicle applications.
Moreover, when using a lithium ion battery, the shape and size of each cell of the battery are often strictly different, and a more flexible heat conductive sheet is required to fill in the difference in the dimensions of each cell.
Furthermore, a sheet material with higher thickness accuracy is required in order to adhere the heat conductive sheet between the heating element such as each cell and the heat sink. However, when the adhesion to the cell is low, the heat conductive performance is low. In addition to this, since vibration cannot be absorbed, there is a problem that the cell may be broken or ignited.

Furthermore, when the resin composition in which the above-mentioned silicone resin is blended with a heat conductive filler is used as the material for the heat conductive sheet, low molecular weight siloxane derived from the silicone resin is generated, and this siloxane is a semiconductor element. It has a problem that it may adhere to a heating element such as the above and cause a contact failure. Furthermore, since the silicone resin is a cross-linked rubber, there is a problem that unevenness in thickness tends to occur when it is cured, and recycling is difficult.
Moreover, the sheet | seat of the heat conductive resin composition using the thermoplastic elastomer mentioned above may not have sufficient physical properties depending on a use. For example, Patent Document 1 discloses performing sheet processing by taking advantage of the characteristics of a thermoplastic elastomer. Specifically, in order to achieve low hardness, a softener such as process oil is blended with an elastomer having a specific structure. However, with the method disclosed in Patent Document 1, it is difficult to obtain a sheet having a high thickness accuracy required in the vehicle field. In particular, when a thermally conductive filler is blended at a high concentration, if it is melt processed by T-die extrusion, torque fluctuation is likely to occur, thickness unevenness occurs, and thickness accuracy decreases. Further, when torque fluctuation occurs during melt processing, productivity is lowered, and it is difficult to efficiently obtain a lot having a quantity per unit. Furthermore, depending on the melt processing conditions, the resin composition pellets as a raw material may not be stably supplied to the processing machine, which may cause further reduction in productivity.

  Therefore, in the present invention, there are provided a resin composition having high thermal conductivity and flame retardancy, flexible, high thickness accuracy, and stable raw material supply capability during sheet production, and a sheet comprising the resin composition. For the purpose.

As a result of intensive studies to solve the above-described problems of the prior art, the present inventors have found that a copolymer containing a conjugated diene unit and a vinyl aromatic compound unit and / or a hydrogenated product thereof, a rubber softener, In addition, the present inventors have found that a resin composition containing a heat conductive filler and a predetermined inorganic substance in a predetermined ratio and a sheet made of the resin composition can solve the above-described problems of the prior art, and completed the present invention. It was.
That is, the present invention is as follows.

[1]
(A) 2-20% by mass of a copolymer containing a conjugated diene unit and a vinyl aromatic compound unit and / or a hydrogenated product thereof,
(B) 2-20% by mass of a rubber softener,
(C) 70 to 95% by mass of a thermally conductive filler,
(D) 0.1 to 3% by mass of at least one additive selected from the group consisting of silica, talc, calcium carbonate, barium sulfate, kaolinite, apatite, diatomaceous earth, zeolite, and mica;
A resin composition comprising:
[2]
The resin composition according to [1], wherein the (C) heat conductive filler has an average particle size of 10 to 150 μm.
[3]
The (C) thermally conductive filler has two or more different maximum values in the particle size distribution, and the difference in particle diameters indicating the respective maximum values is 50 μm or more, [1] or [2 ] The resin composition as described in above.
[4]
As the (C) thermally conductive filler,
(CI) a first thermally conductive filler having an average particle size of 60 μm or more and 150 μm or less;
(C-II) The resin composition according to any one of [1] to [3] above, which contains a second thermally conductive filler having an average particle diameter of 5 μm or more and 60 μm or less.
[5]
The mass ratio ((C-I) / (C-II)) of the (C-I) component to the (C-II) component is 100/1 to 100/170, as described in [4] above. Resin composition.
[6]
Wherein (C) Na ₂ O concentration in the thermally conductive filler is 1.00% by mass or less exceed 0.20 wt%, the resin composition according to any one of [1] to [5] object.
[7]
The content of the vinyl aromatic compound unit in the copolymer (A) and / or hydrogenated product thereof is less than 30% by mass,
[B] The mass ratio of (A) copolymer and / or hydrogenated product thereof ((A) / (B)) to (B) rubber softener is 35/65 to 60/40. [6] The resin composition according to any one of [6].
[8]
[1] The thermally conductive filler (C) is at least one selected from the group consisting of metal nitrides not containing silicon, metal oxides not containing silicon, and metal hydroxides not containing silicon. ] The resin composition as described in any one of [7].
[9]
The resin composition according to any one of [1] to [8], wherein the (C) thermally conductive filler is aluminum hydroxide or alumina.
[10]
The resin composition according to any one of [1] to [9], wherein the (D) additive is silica or talc.
[11]
(E) The resin composition according to any one of [1] to [10], further including 0.01 to 2% by mass of a plasticizer.
[12]
Resin composition as described in any one of said [1] thru | or [11] whose hardness by durometer type A is less than 60 based on JISK6253-3.
[13]
The sheet | seat which is 0.1-10 mm in thickness including the resin composition as described in any one of said [1] thru | or [12].
[14]
The sheet according to [13], wherein the water content is 200 ppm or less.

  According to the present invention, a resin composition having high thermal conductivity, flame retardancy, and vibration absorption, flexible, high thickness accuracy, stable raw material supply capability during sheet production, and excellent sheet productivity. The sheet | seat which consists of a thing and the said resin composition is obtained.

The schematic block diagram of an example of the battery module for evaluating the characteristic of the resin composition of this embodiment is shown.

Hereinafter, modes for carrying out the present invention (hereinafter referred to as “the present embodiment”) will be described in detail.
In addition, the following this embodiment is an illustration for demonstrating this invention, and does not limit this invention to the following content. The present invention can be appropriately modified within the scope of the gist.

(Resin composition)
The resin composition in the present embodiment is
(A) 2-20% by mass of a copolymer containing a conjugated diene unit and a vinyl aromatic compound unit and / or a hydrogenated product thereof (hereinafter sometimes referred to as “component (A)”);
(B) 2-20% by mass of a rubber softener (hereinafter sometimes referred to as “component (B)”),
(C) Thermally conductive filler (hereinafter may be referred to as “component (C)”) 70 to 95% by mass;
(D) At least one additive selected from the group consisting of silica, talc, calcium carbonate, barium sulfate, kaolinite, apatite, diatomaceous earth, zeolite, and mica (hereinafter referred to as “(D) component”). And 0.1) to 3% by mass,
Is a resin composition.

  Here, “and / or” in the component (A) may include both a copolymer containing a conjugated diene unit and a vinyl aromatic compound unit and a hydrogenated product, and includes only one of them. It means that you may go out.

Moreover, each component contained in the resin composition of this embodiment may be used individually by 1 type, respectively, and may use 2 or more types together.
The resin composition of the present embodiment has thermal conductivity, flame retardancy, and stable raw material supply capability during sheet production by blending the components (A) to (D) at a characteristic ratio.
Furthermore, the resin composition of the present embodiment has two or more different maximum values in the particle size distribution as the component (C), and the difference in particle diameters indicating the respective maximum values is 50 μm or more. It is preferable to use a thermally conductive filler. Thereby, a sheet having excellent flexibility and high thickness accuracy can be obtained.

((A) Copolymer containing conjugated diene unit and vinyl aromatic compound unit and / or hydrogenated product thereof)
The resin composition of this embodiment contains a copolymer containing a conjugated diene unit and a vinyl aromatic compound unit and / or a hydrogenated product thereof as the component (A).
As the component (A), a copolymer obtained by copolymerizing a conjugated diene and a vinyl aromatic compound can be used.
As the component (A), a styrene thermoplastic elastomer and a hydrogenated product thereof are preferable from the viewpoints of flexibility such as hardness and tensile elongation at break.
Styrenic thermoplastic elastomers and hydrogenated products thereof are not limited to the following. For example, styrene-butadiene-styrene block copolymer (SBS), styrene-isoprene-styrene block copolymer (SIS). , Styrene-ethylene-butylene-styrene block copolymer (SEBS), styrene-ethylene-propylene-styrene block copolymer (SEPS), styrene-ethylene-ethylene-propylene-styrene copolymer ((SEEPS), styrene- Examples thereof include butadiene random copolymers and hydrogenated products thereof.
Among these, from the viewpoint of flexibility, a hydrogenated product of a styrene-based thermoplastic elastomer is preferable, a hydrogenated product of a styrene-ethylene / butylene-styrene block copolymer, and a styrene-ethylene / propylene-styrene block copolymer. More preferred are hydrogenated products and hydrogenated products of styrene-ethylene / ethylene / propylene / styrene block copolymers.

As the conjugated diene, any diolefin having a pair of conjugated double bonds (two double bonds bonded so as to be conjugated) may be used.
Examples of the conjugated diene include, but are not limited to, 1,3-butadiene, 2-methyl 1,3-butadiene, 2-methyl-1,3-butadiene (isoprene), 2,3-dimethyl, for example. -1,3-butadiene, 1,3-pentadiene, 2-methyl-1,3-pentadiene, 1,3-hexadiene and the like. Among these, 1,3-butadiene and 2-methyl-1,3-butadiene (isoprene) are preferable from the viewpoint of versatility. These may be used individually by 1 type and may use 2 or more types together.
As the vinyl aromatic unit, any compound having a vinyl group and an aromatic ring may be used. Examples of the vinyl aromatic compound include, but are not limited to, styrene, α-methylstyrene, p-methylstyrene, o-divinylbenzene, m-divinylbenzene, p-divinylbenzene, 1,1- Examples include diphenylethylene, N, N-dimethyl-p-aminoethylstyrene, N, N-diethyl-p-aminoethylstyrene, and the like. These may be used individually by 1 type and may use 2 or more types together.

The content of the vinyl aromatic compound unit in the component (A) is preferably less than 30% by mass, more preferably 20% by mass or less, and further preferably 15% by mass or less.
In the copolymer of component (A) or a hydrogenated product thereof, a polymer block of vinyl aromatic compound units usually exists as a hard segment, and a polymer block of conjugated diene units exists as a soft segment.
The copolymer of component (A) exhibits rubber-like properties because the hard segment acts as a physical cross-linking point of the soft segment below its glass transition temperature. On the other hand, the soft segment plays an important role in the incorporation of the filler, and when the content of the soft segment in the copolymer is high, that is, when the content of vinyl aromatic compound units is low, the increase in the filler content There is a tendency for the hardness of the copolymer to hardly increase.
Therefore, if the content of the vinyl aromatic compound unit in the component (A) is within the above numerical range, a resin composition having a low hardness is preferable even if the content of the heat conductive filler (C) described later is large. (However, the action mechanism of this embodiment is not limited to the above. The same applies to the following description of the action mechanism.)
In addition, content of the vinyl aromatic compound unit in (A) component can be controlled by adjusting the addition amount of the monomer in the polymerization process of a copolymer, and a nuclear magnetic resonance apparatus (NMR) is used. Can be measured. Specifically, it can be measured by the method described in the examples.

The weight average molecular weight of (A) component is not specifically limited. Preferably ^{5 × 10 4 ~100 × 10 4} , more preferably from ^{8 × 10 4 ~80 × 10 4} , more preferably from ^{9 × 10 4 ~30 × 10 4} .
When the weight average molecular weight is 5 × 10 ⁴ or more, the toughness of the resin composition of the present embodiment is improved and a smaller compression set is exhibited. Moreover, when the weight average molecular weight is 100 × 10 ⁴ or less, the flexibility of the resin composition of the present embodiment is improved.
The weight average molecular weight of the component (A) can be measured by gel permeation chromatography (GPC). Specifically, it can be calculated from the molecular weight of the peak of the chromatogram using a calibration curve calculated from measurement of commercially available standard polystyrene.

When the component (A) contains a hydrogenated copolymer (hereinafter also referred to as “hydrogenated copolymer”), the hydrogenation rate of double bonds based on the conjugated diene of the copolymer before hydrogenation Is preferably 10% or more, more preferably 75% or more, and still more preferably 85% or more. When the hydrogenation rate is in the above numerical range, it is possible to suppress a decrease in flexibility, strength, elongation, and the like due to thermal deterioration, and to show better heat resistance.
The hydrogenation rate of the double bond based on the conjugated diene refers to the ratio of the hydrogenated double bond to the double bond of the conjugated diene contained in the copolymer before hydrogenation. In addition, the hydrogenation rate of a hydrogenated copolymer can be measured using a nuclear magnetic resonance apparatus (NMR). Specifically, it can be measured by the method described in the examples.

((B) Rubber softener)
The resin composition of this embodiment contains a rubber softener as the component (B).
The component (B) is not limited to the following, but for example, a mineral oil-based rubber softener or a synthetic rubber softener used for the purpose of softening, increasing volume, improving processability, etc. Etc.
Examples of the mineral oil-based rubber softener include, but are not limited to, process oil and extender oil. Specific examples include a mixture containing any two or more selected from the group consisting of a compound having an aromatic ring, a compound having a naphthene ring, and a compound having a paraffin chain.
Examples of synthetic rubber softeners include, but are not limited to, silicone oils and fluorine oils.
The component (B) is preferably paraffinic oil, naphthenic oil, or aromatic oil, more preferably paraffinic oil or naphthenic oil, and more preferably from the viewpoint of improving the softness and processability of rubber. It is a paraffinic oil. Among paraffinic oils, oils with less aromatic components are particularly preferable from the viewpoint of cold resistance and durability. These may be used individually by 1 type and may use 2 or more types together.
Kinematic viscosity at 40 ° C. of paraffin oil is preferably at least 100 mm ² / sec, more preferably 100~10000mm ² / sec, more preferably 200~5000mm ² / sec. When the kinematic viscosity of the paraffinic oil is within the above numerical range, the affinity with rubber is good and the oil tends to hardly bleed. Kinematic viscosity is measured by measuring the time (sec: absolute viscosity) required for a specific volume of oil to flow down naturally through a capillary of a viscometer (for example, “Fenske viscometer” manufactured by Canon). It can be calculated by dividing the absolute viscosity by the material density.
A commercially available product can also be used as the paraffinic oil. Examples of commercially available products include, but are not limited to, “NA Solvent” manufactured by Nippon Oil & Fats, “Diana Process Oil PW-90”, “Diana Process Oil PW-380” manufactured by Idemitsu Kosan Co., Ltd., and Idemitsu Oil. “IP-solvent 2835” manufactured by Kagaku Co., “Neothiozole” manufactured by Sanko Chemical Co., Ltd. and the like can be mentioned.

  The flash point of the component (B) is preferably 170 to 300 ° C. The flash point is a Cleveland open method flash point tester, a sample cup is filled with a specified amount of sample and heated, and a test flame is passed over the sample cup at a specified temperature interval to ignite the vapor of the material. , By measuring the minimum temperature of the sample when the flame propagates on the liquid surface. When the flash point of (B) component exists in the said numerical range, it exists in the tendency for the flame retardance of the resin composition of this embodiment to improve.

  (B) As for the weight average molecular weight of a component, 100-5000 are preferable. The weight average molecular weight can be measured by GPC. When the weight average molecular weight of (B) component is the said numerical range, it exists in the tendency which is low volatility and can provide a sufficient softening effect to a resin composition.

((C) Thermally conductive filler)
The resin composition of this embodiment contains a thermally conductive filler as the component (C).
The thermally conductive filler is a particulate or powdery substance whose main component is an inorganic material or metal having a high thermal conductivity.
(B) A heat conductive filler is mix | blended in order to improve a heat conductivity by forming a heat conduction path inside the resin composition of this embodiment.
The component (C) is not limited to the following, but includes metal nitrides, metal oxides, and metal hydroxides. The thermal conductivity of the resin composition of the present embodiment, the resin composition, and the sheet. From the viewpoints of productivity, handling, and availability, it is selected from the group consisting of silicon-free metal nitrides, silicon-free metal oxides, and silicon-free metal hydroxide metal compounds. At least one is preferred.
When silicon is contained in the metal compound, the thermal conductivity of the metal compound is lowered, and as a result, the thermal conductivity of the resin composition is lowered, which is not preferable. Even if it contains a trace amount of impurity components derived from these raw materials, it does not matter.
The metal nitride is not limited to the following, and examples thereof include boron nitride and aluminum nitride.
The metal oxide is not limited to the following, and examples thereof include alumina, magnesium oxide, zinc oxide, zirconium oxide, calcium oxide and the like.
The metal hydroxide is not limited to the following, and examples thereof include aluminum hydroxide, magnesium hydroxide, zinc hydroxide, calcium hydroxide, and tin hydroxide.

As the component (C), aluminum hydroxide, magnesium hydroxide, and alumina are preferable. More preferred are aluminum hydroxide and alumina.
By using aluminum hydroxide or magnesium hydroxide as the component (C), not only thermal conductivity but also flame retardancy tends to be improved. Further, by using alumina as the component (C), even when the filler content is low, thermal conductivity tends to be obtained efficiently. Alumina has high thermal conductivity, tends to impart high thermal conductivity to the resin composition, and tends to provide a good balance between flexibility and thermal conductivity.

  Component (C) may be appropriately pretreated. For example, the above-described metal compound may be pretreated with a silane coupling agent, a titanate coupling agent, stearic acid, or the like and subjected to surface modification.

The component (C) has an average particle size of preferably 10 to 150 μm, more preferably 20 to 100 μm, still more preferably 25 to 25 from the viewpoints of thermal conductivity, productivity at the time of compounding, and sheet production. 80 μm.
As described above, the thermally conductive filler of component (C) has two or more different maximum values in the particle size distribution, and the difference in particle diameter indicated by each maximum value may be 50 μm or more. Preferably, it is 55 μm or more, more preferably 60 μm or more. When the difference in the particle diameter indicated by the maximum value is 50 μm or more, a sheet with more flexibility can be obtained, and the extrusion stability when processed into a sheet shape is increased. Tend to be able to get.

As the component (C), it is preferable to use a plurality of thermally conductive fillers having different average particle sizes.
More preferably, (CI) a first thermal conductive filler having an average particle size of 60 μm or more and 150 μm or less, and (C-II) a second thermal conductivity having an average particle size of 5 μm or more and 60 μm or less. A thermally conductive filler containing a filler is used. Thereby, it exists in the tendency which can obtain the composition excellent in the balance of a flame retardance and a softness | flexibility.
The difference in average particle size between (CI) and (C-II) is preferably 50 μm or more from the viewpoint of flame retardancy, sheet processability, thickness accuracy, and vibration absorption.

  The mass ratio of the (CI) component to the (C-II) component ((CI) / (C-II)) is preferably 100/1 to 100/170, more preferably 100/10 to 100/170, more preferably 100/20 to 100/150, and even more preferably 100/25 to 100/120. When the mass ratio of the (CI) component to the (C-II) component ((CI) / (C-II)) is in the numerical range, the thermal conductivity and flame retardancy tend to improve in a well-balanced manner. is there.

The component (C) is preferably in the form of particles. The particle shape referred to here is, for example, a spherical shape, a shape in which spheres are aggregated, a shape in which spheres are flattened, a shape in which flattened spheres are aggregated, an irregular crushing shape, a shape in which amorphous crushing material is agglomerated, a hole It refers to a foamed shape having a shape and a shape obtained by granulating these shapes.
In particular, when the component (C) has a particle shape and the average particle diameter is in the above range, the thermal conductivity tends to be more effectively expressed.
The average particle diameter is an average value of volume-based particle diameters measured using a laser diffraction / scattering particle size distribution measuring apparatus. The particle size is usually measured by dispersing a thermally conductive filler in water or ethanol. At this time, if it cannot be dispersed, a surfactant may be used as appropriate, or it may be dispersed by a homogenizer or ultrasonic waves. The concentration of the thermally conductive filler dispersed at this time is usually 1% by mass or less.

Component (C), Na ₂ O concentration is preferably 1.00 mass% or less exceed 0.20 wt%. More preferably, it is 0.50 mass% or less, More preferably, it is 0.35 mass% or less.
From the viewpoint of the dielectric breakdown strength of the resin composition of the present embodiment, the Na ₂ O concentration in the component (C) is preferably 1.00% by mass or less. Further, the lower limit of the Na ₂ O concentration in the component (C) is not particularly limited, but an amount exceeding 0.20% by mass is preferable from the viewpoint of productivity. In order to make it 0.2 mass% or less, processing, such as refine | purifying (C) component, is required, and it exists in the tendency from the surface of productivity for obtaining a heat conductive filler.
The concentration of Na ₂ O in component (C) can be determined by fluorescent X-ray spectroscopy.

((D) Additive)
The resin composition of this embodiment contains at least one additive selected from the group consisting of silica, talc, calcium carbonate, barium sulfate, kaolinite, apatite, diatomaceous earth, zeolite, and mica as the component (D).
Component (D) is added for the purpose of a flame retardant aid. A flame retardant aid is a resin and / or a component added to improve flame retardancy, which is generated at the time of combustion. It is a component added for this purpose. For example, when fumed silica is used as a flame retardant aid and aluminum hydroxide is used as a component that exhibits flame retardancy, water vapor is generated from the aluminum hydroxide when the resin composition burns, and the generated water vapor is Silica diffuses on the surface of the resin composition, and flame retardance is improved by efficiently blocking oxygen as a combustion support from the surface of the resin composition.
Furthermore, (D) component is added also for the purpose as an antiblocking agent. The anti-blocking agent means that the component (A) and / or the component (B) are bonded to the raw materials of the resin composition or bonded between the resin compositions, and the raw material and the resin composition are produced. It is a component added for the purpose of preventing random adhesion to a machine hopper or screw. The component (A) and / or the component (B) are bonded to the raw materials of the resin composition, bonded to each other between the resin compositions, or the raw material and the resin composition are randomly added to the hopper or screw of the production machine. When it adheres, it may be difficult to continuously supply a certain amount of the raw material of the resin composition or the resin composition during production. Moreover, when the resin composition is a pellet, the pellet is fixed when the pellet is stored, and it may be necessary to provide a step of crushing again before forming the sheet. By using the component (D), such inconvenience can be prevented.
That is, by adding the component (D), it is possible to obtain a resin composition having an improved balance of thermal conductivity and flame retardancy and having a stable raw material supply capability during sheet production.

As described above, the component (D) comprises at least one selected from the group consisting of silica, talc, calcium carbonate, barium sulfate, kaolinite, apatite, diatomaceous earth, zeolite, and mica.
These may be used alone or in combination of two or more.
(D) A well-known material can be used for a component, and any of a natural product and a synthetic material may be sufficient as it. In use, commercially available products can also be used because of their availability. Moreover, as long as the object of the present invention is not impaired, the component (D) may contain a trace amount of an impurity component derived from a natural product or a raw material of a synthetic product.

  The component (D) is preferably in the form of particles. The particle shape here is, for example, a sphere, a shape in which spheres are aggregated, a shape in which spheres are flattened, a shape in which flattened spheres are agglomerated, an irregularly crushed shape, a shape in which irregularly crushed materials are aggregated, It refers to a foamed shape having holes and a shape obtained by granulating these shapes. Moreover, it may be porous, and small particles may be aggregated to be substantially porous. (D) It exists in the tendency for the effect as a flame retardant adjuvant and an antiblocking agent to express more efficiently because a component is the above shapes.

As the component (D), silica, talc, diatomaceous earth, and zeolite are preferable because they are highly effective in improving the flame retardancy with respect to the added amount and improving the ability to stably supply raw materials during sheet production. Particularly preferred is silica or talc.
When silica is used as the component (D), either crystalline silica or amorphous silica may be used.
Typical examples of crystalline silica include quartz, quartz, tridymite, cristobalite, coachite, stishovite and the like. Typical examples of the amorphous silica include quartz glass, silica gel, kitite, and fibrous silica W having a siloxane chain formed by oxidation of silicon monoxide. Among these, amorphous silica is preferable because it can provide a good balance between thermal conductivity and flame retardancy. Furthermore, among these, fumed silica is particularly preferable because it has a high effect of obtaining a resin composition having a stable raw material supply capability during sheet production.
A commercial item can also be used as fumed silica. Examples of commercially available products include, but are not limited to, "Aerosil 130", "Aerosil 200", "Aerosil 300", "Aerosil R106", manufactured by Nippon Aerosil Co., Ltd. “CAB-O-SIL”, “CAB-O-SPERSE” and the like.
(D) When using talc as a component, a commercial item can also be used. Commercially available products are not limited to the following, for example, “Nanoace” grades (hereinafter referred to as series) manufactured by Nippon Talc, “SG” series, “Microace” series, “MS-P” series , “MS-K” series, “SWE” series, “Simgon” series, “SSS” series, “RA” series, “PA-OG” series, “FT” series, “MF” series manufactured by Fukuoka Talc Industrial Co., Ltd. , "PS" series, Matsumura Sangyo "Crown Talc" series, "High Filler" series, Fuji Talc Kogyo "FH" series, "FL" series, "FG" series, "FS" series, "ML" Series, “MG” series, “MS” series, “RL” series, “RG” series, “RH” series, “RS” series And the like.

  The component (D) may be appropriately pretreated as long as it does not impair the object of the present invention. For example, the above-described silica may be pretreated with a silane coupling agent, a titanate coupling agent, stearic acid, or the like to perform surface modification.

((E) Plasticizer)
The resin composition in the present embodiment preferably further contains (E) a plasticizer from the viewpoint of obtaining better flexibility.
The plasticizer is not particularly limited as long as it can impart plasticity to the resin composition, and examples thereof include phthalic acid esters, aliphatic carboxylic acid esters, polyester polymer plasticizers, and higher fatty acids. Higher fatty acid esters, higher aliphatic amides, higher fatty acid metal salts, and the like. Here, the higher fatty acid means a fatty acid having 6 or more carbon atoms.
Among these, higher fatty acids are preferable, myristic acid, pentadecylic acid, palmitic acid, margaric acid, stearic acid, tuberculostearic acid, and arachidic acid are more preferable, and palmitic acid and stearic acid are more preferable.

((F) fluororesin and / or modified fluororesin)
The resin composition of the present embodiment may further contain (F) a fluorine resin and / or a modified fluorine resin.
When the resin composition of the present embodiment contains (F) a fluororesin and / or a fluororesin-modified product, these components are efficiently dispersed in a fibrous form (fibril form), so that the physical properties of the fibrils are increased. Network tends to be formed and the melt tension of the resin composition tends to be improved. As a result, the processability of the resin is improved, and anti-dripping properties (for example, suppression of flame drops during combustion can be mentioned, which is effective in suppressing fire spread).

As the component (F), from the viewpoint of fibril forming ability, for example, tetrafluoroethylene polymers such as polytetrafluoroethylene and tetrafluoroethylene / propylene copolymers are preferable, and polytetrafluoroethylene is more preferable.
The form of the component (F) is not particularly limited, and any suitable one can be adopted depending on the purpose and application. For example, fine powder fluorine resin, aqueous dispersion of fluorine resin, powder mixture with other resins such as acrylonitrile-styrene copolymer resin (AS resin) and polymethyl methacrylate (PMMA) (acrylic modification of fluorine resin) (Hereinafter also referred to as “modified fluororesin”)).

As the fluorine resin modified product, an acrylic modified product of polytetrafluoroethylene (PTFE) is preferable from the viewpoint of anti-dripping performance and roll peelability during sheet processing.
The acrylic modified product contains polytetrafluoroethylene and a (meth) acrylic acid alkyl ester polymer as main components. The acrylic modified product is, for example, a (meth) acrylic acid alkyl ester having an alkyl group having 1 to 4 carbon atoms in a dispersion in which polytetrafluoroethylene particles having an average particle size of 0.05 to 1.0 μm are dispersed. It is obtained by polymerizing a monomer containing 70 mass% or more to form a (meth) acrylic acid alkyl ester polymer, and then solidifying or spray-drying the solid content in the dispersion. Further, for example, a structural unit comprising a dispersion in which polytetrafluoroethylene particles having an average particle diameter of 0.05 to 1.0 μm are dispersed, and a (meth) acrylic acid alkyl ester having an alkyl group having 1 to 4 carbon atoms. After mixing with a dispersion in which (meth) acrylic acid alkyl ester polymer particles containing 70% by mass or more are dispersed, the solid content in the mixed dispersion is obtained by coagulation or spray drying.
Commercially available products can also be used as the modified fluororesin, and examples thereof include “Metablene (trademark) A-3800” and “Metablene (trademark) A-3750” manufactured by Mitsubishi Rayon Co., Ltd.

Content of the (A) component in the resin composition of this embodiment is 2-20 mass%, Preferably it is 2-15 mass%, More preferably, it is 4-10 mass%.
When the content of the component (A) is 20% by mass or less, sufficient thermal conductivity and flame retardancy can be obtained. Moreover, favorable moldability is obtained because content of (A) component is 2 mass% or more.

Content of (B) component in the resin composition of this embodiment is 2-20 mass%, Preferably it is 4-20 mass%, More preferably, it is 6-14 mass%.
When the content of the component (B) is 20% by mass or less, bleeding out of the component (B) can be prevented, and sufficient flame retardancy can be obtained. Moreover, when the content of the component (B) is 2% by mass or more, the resin composition has a sufficiently low hardness.

The mass ratio of component (A) to component (B) ((A) / (B)) is preferably 35/65 to 60/40, more preferably 35/65 to 50/50, and even more preferably. Is 35/65 to 45/55.
When the mass ratio of the component (A) to the component (B) ((A) / (B)) is 35/65 or more (the ratio of the component (A) increases), the bleeding out of the component (B) And high flame retardancy can be obtained.
Further, when the mass ratio of the component (A) to the component (B) ((A) / (B)) is 60/40 or less (the ratio of the component (A) is small), the resin composition is sufficiently low. It tends to become hardness.

Content of (C) component in the resin composition of this embodiment is 70-95 mass%, Preferably it is 75-90 mass%, More preferably, it is 75-85 mass%.
When the content of the component (C) is 70% by mass or more, sufficient thermal conductivity and flame retardancy are obtained. Further, when the content of the component (C) is 95% by mass or less, the resin composition has a sufficiently low hardness.

Content of (D) component in the resin composition of this embodiment is 0.1-3 mass%, Preferably it is 0.1-2 mass%, More preferably, it is 0.5-2 mass%. is there.
When the content of the component (D) is 0.1% by mass or more, a stable raw material supply capability can be obtained during sheet production. Further, when the content of the component (D) is 3% by mass or less, a stable raw material supply capability at the time of sheet production can be obtained. Furthermore, sufficient flexibility can be obtained.

  Content of (E) component in the resin composition of this embodiment becomes like this. Preferably it is 0.01-2 mass%, More preferably, it is 0.1-1.5 mass%, More preferably, it is 0.00. 3 to 1% by mass. When content of (E) component exists in the said range, a resin composition becomes low hardness and exists in the tendency for sheet moldability (viscosity and roll adhesiveness) to be improved.

  Content of the (F) component in the resin composition of this embodiment becomes like this. Preferably it is 0.01-5 mass%, More preferably, it is 0.1-2 mass%, More preferably, it is 0.3- 1.5% by mass. When content of (F) component exists in the said range, it exists in the tendency for a flame retardance, a mechanical characteristic, and sheet moldability (viscosity and roll adhesiveness) to be improved.

About the resin composition of this embodiment, the hardness measured using durometer type A according to JIS K6253-3 is preferably less than 60, more preferably less than 40, and even more preferably less than 30. is there.
When the hardness of the resin composition is in the above range, when a sheet obtained from the resin composition is used as a heat conductive sheet, stress on the heating element can be effectively reduced and the dimensional tolerance of the component is absorbed. The heat dissipation function tends to be expressed efficiently.

(Other ingredients)
About the resin composition of this embodiment, you may further contain a tackifier as needed in the range which does not impair the objective of this invention.
For example, when the resin composition of this embodiment is used in the form of a sheet, the tackifier is added to fix the electronic component, the semiconductor device or the display device, and the heat dissipation device. It does not specifically limit as a tackifier, A conventionally well-known thing can be used. Examples thereof include rosin resins, modified rosin resins, rosin ester resins, petroleum resins, terpene resins, coumarone / indene resins, phenol resins, xylene resins, and the like. These may be used individually by 1 type and may use 2 or more types together. These tackifiers may be contained in the entire resin composition or may be present only in the surface layer of the sheet.
The resin composition of the present embodiment may further contain other additives such as an antioxidant, a crosslinking agent, a thermoplastic resin other than those described above, and rubber as necessary.
Examples of the antioxidant include, but are not limited to, for example, 1,2-dihydro-2,2,4-trimethylquinoline, N-isopropyl-N′-phenyl-p-phenylenediamine, diphenyl-p. -Phenylenediamine, octylated diphenylamine and the like.
Examples of the crosslinking agent include, but are not limited to, 2,5-dimethyl-2,5-bis (tert-butylperoxy) hexane, 2,5-dimethyl-2,5-bis (tert -Butylperoxy) -3-hexyne, 1,3-bis (tert-butylperoxyisopropyl) benzene and the like.
The thermoplastic resin other than the above is not limited to the following, and examples thereof include polyethylene, polypropylene, (meth) acrylic resin, and polystyrene.
Examples of the rubber include, but are not limited to, isoprene rubber, styrene-butadiene rubber, butadiene rubber, and styrene-isoprene-butadiene rubber.

  It is also one of the preferred embodiments that the resin composition of the present embodiment is combined with a fabric such as glass fiber cloth or organic fiber cloth. In particular, when the resin composition of this embodiment is made into a sheet, the composite with glass fiber cloth not only can further improve the strength, dimensional stability, and flame retardancy of the thin wall, but can also be provided as a thin sheet. Therefore, the thermal resistance value of the sheet tends to be reduced.

(Production method of resin composition)
The resin composition of this embodiment can be manufactured by kneading each component mentioned above. The kneading method is not particularly limited, and a conventionally known method can be applied. For example, a blade type kneader (kneader, Banbury mixer, etc.), a roll type kneader (two rolls, three rolls, roll mill, taper roll, etc.), a screw type kneader (extruder, etc.), etc. can be used. . Among these, it is preferable to use a pressure kneader, a Banbury mixer, an extruder, or the like.

(Use of resin composition)
The resin composition of this embodiment can be used for various uses.
At that time, the shape of the resin composition can be appropriately changed according to the application. Especially, it is preferable to use the resin composition of this embodiment as sheets, such as a thermal radiation sheet, and it is especially suitable as a thermal radiation sheet for lithium batteries.

Although the thickness of the sheet | seat obtained from the resin composition of this embodiment is not specifically limited, It is preferable that it is 0.1-10 mm, More preferably, it is 0.2-5 mm, More preferably, it is 0.3-3 mm It is. A sheet having a thickness in the numerical range can be suitably used as a heat dissipation sheet for a battery.
When the thickness of the sheet is 0.1 mm or more, there is a tendency to efficiently fill the difference in dimensions of the heating elements on the substrate and to efficiently dissipate heat. Moreover, when the thickness of the sheet is 10 mm or less, the thermal resistance value can be kept low, and sufficient heat dissipation tends to be exhibited.

When making the resin composition of this embodiment into a sheet | seat, it is preferable that the moisture content (water content) of a sheet | seat is 200 ppm or less. When the moisture content of the sheet is 200 ppm or less, the extrusion processability is stable and a sheet with high thickness accuracy tends to be obtained. In order to reduce the moisture content of the sheet to 200 ppm or less, a method of controlling the moisture content contained in the resin composition in advance and feeding it into a molding machine, a method of vacuum devolatilization when the resin composition is melt processed, etc. Among them, a method in which the amount of water contained in the resin composition is previously controlled to 1000 ppm or less and charged into a molding machine is preferably used.
Here, the amount of water contained in the sheet or the resin composition can be measured by a Karl Fischer moisture meter.

The sheet obtained from the resin composition of the present embodiment may be a single layer or a multilayer.
When it is a multilayer, each layer may be the same composition or different. The thickness of the entire multilayer sheet is preferably within the above thickness range. The thickness of the entire multilayer sheet is preferably within the above thickness range. As a manufacturing method of a multilayer sheet, you may shape | mold using a multilayer extruder, and you may make it closely_contact | adhere by performing heating, pressurization, etc., after laminating | stacking without using an adhesion layer.
When the resin composition is a sheet, an adhesive layer may be provided on one or both surfaces. For the formation of the adhesive layer, a method such as sticking or coating (coating) can be used. Although it does not specifically limit as a component of an adhesion layer, For example, it can be set as the adhesion layer containing an acrylic adhesive. The adhesive layer may further contain a flame retardant and other components.
The sheet obtained from the resin composition of the present embodiment may be wound into a roll with a release film or a transfer type adhesive film interposed therebetween. It does not specifically limit about the magnitude | size of a sheet | seat, It can process into a desired magnitude | size according to a use.

It does not specifically limit as a method of processing a resin composition into a sheet | seat, For example, extrusion molding, compression molding, calendar molding etc. are mentioned. Among these, extrusion molding and calender molding are preferable from the viewpoint that they can be continuously formed and winding is easy.
More preferable sheet production methods include a method of forming a sheet by extruding it into a T-die while kneading each component with an extruder, and winding the sheet together with a release film or a transfer type adhesive film using a sheet take-up device. . Extrusion conditions vary depending on the raw materials used and the width of the sheet to be formed, but the set temperature of the extruder is 80 to 190 ° C., the screw rotation speed is 5 to 80 rpm, and the L / D ratio (screw to screw diameter (L)) Is preferably adjusted to 20 or more.
In addition, the resin composition is dissolved / dispersed in a solvent, poured onto a film or release paper, then stripped of the solvent to obtain a sheet, or impregnated with glass fiber cloth or organic fiber cloth, and then the solvent is removed. It is also possible to obtain a sheet by doing so.

The resin composition and its sheet in the present embodiment can be used for various electric / electronic parts, semiconductor devices, display devices, communication devices, power devices, and the like. More specifically, computer CPU, liquid crystal backlight, plasma display panel, LED element, secondary battery or its peripheral device, Peltier element, thermoelectric conversion element, temperature sensor, converter, transformer, inverter, (high) power transistor Etc. The secondary battery referred to here may be a nickel-cadmium battery or a lithium ion battery. Further, the shape of the lithium ion battery may be a rectangular flat shape, a cylindrical shape, or a laminate shape.
When using the sheet | seat obtained from the resin composition of this embodiment as a heat radiating sheet for lithium ion batteries, as long as it can transfer the heat which generate | occur | produces from a cell, you may use it anywhere. If it aims at the dimension absorption of a lithium ion battery, you may use between a cell and a heat sink.

  Hereinafter, the present embodiment will be specifically described with reference to specific examples and comparative examples, but the present embodiment is not limited to the following examples.

The following were used as each component which comprises a resin composition.
〔material〕
<(A) Copolymer containing conjugated diene unit and vinyl aromatic compound unit and / or hydrogenated product thereof>
(A-1) (hydrogenated styrene-ethylene-butylene-styrene block copolymer (SEBS))
"Tuftec (registered trademark) H1221", manufactured by Asahi Kasei Corporation (vinyl aromatic compound unit content: 12% by mass, hydrogenation rate: 99%)
(A-2) (hydrogenated styrene-ethylene / ethylene / propylene block copolymer (SEEPS))
“Hibler (registered trademark) 7311”, manufactured by Kuraray Co., Ltd. (content of vinyl aromatic compound unit: 12% by mass, hydrogenation rate: 99%)
(A-3) (hydrogenated styrene-butadiene random copolymer)
“SOE (registered trademark) L606”, manufactured by Asahi Kasei Corporation (content of vinyl aromatic compound unit: 52 mass%, hydrogenation rate: 99%)

<(B) Rubber softener>
(B-1) Paraffin-based process oil “Diana Process Oil (trademark) PW-380”, manufactured by Idemitsu Kosan Co., Ltd.

<(C) Thermally conductive filler>
(Aluminum hydroxide)
(C-1) “SB73”, manufactured by Nippon Light Metal Co., Ltd. (average particle size 85 μm, Na ₂ O content 0.25 mass%)
(C-2) “SB303”, manufactured by Nippon Light Metal Co., Ltd. (average particle size 25 μm, Na ₂ O content 0.25 mass%)
(C-2) “SB153”, manufactured by Nippon Light Metal Co., Ltd. (average particle size 10 μm, Na ₂ O content 0.26 mass%)

<(D) Silica>
(Fumed silica)
(D-1) "Aerosil (trademark) 200", manufactured by Nippon Aerosil Co., Ltd.

<(E) Plasticizer>
(Higher fatty acid)
(E-1) Stearic acid “Stearic acid 300”, manufactured by Shin Nippon Chemical Co., Ltd.

<(F) Acrylic modified PTFE>
(F-1) Acrylic modified polytetrafluoroethylene (PTFE)
"Metablene (trademark) A-3800", manufactured by Mitsubishi Rayon Co., Ltd.

The sheet was produced according to the following method.
[Sheet Manufacturing Method]
<Kneading process>
The raw materials were melt kneaded using a 48 mm twin screw extruder. While the raw material was quantitatively fed from each feeder, pellets of the resin composition were obtained under the conditions of a cylinder temperature of 160 ° C., a screw rotation speed of 170 rpm, and a discharge amount of 150 kg / hr.
<Sheet processing>
Using a 65 mm single screw extruder provided with a 600 mm wide T-die, the resin composition pellets obtained in the kneading step were processed into a sheet.
The cylinder temperature and the die temperature are set to 110 ° C., the roll temperature is set to 50 ° C., the resin composition pellets are extruded into a sheet shape by a T-die while being melted by an extruder, and cooled to a predetermined thickness by rolling with a roll. A sheet having about 1.5 mm) was obtained.

The physical properties and characteristics were measured by the following methods.
〔Measuring method〕
<Content of vinyl aromatic compound unit>
The content of the vinyl aromatic compound unit in the component (A) was measured by a nuclear magnetic resonance apparatus (NMR). Specifically, using a nuclear magnetic resonance apparatus (NMR, ECA-500: manufactured by JEOL Ltd.), Y. Tanaka, et al. , Rubber Chemistry and Technology 54.685 (1981). A sample prepared by dissolving 30 mg of the copolymer in 1 g of deuterated chloroform was used.

<Hydrogenation rate>
The hydrogenation rate of component (A) was measured by nuclear magnetic resonance NMR (“ADVANCE 600 MHz”).

<Particle size / size distribution / average particle size>
Using a laser diffraction / scattering particle size distribution analyzer (“Microtrack MT3300EX-II” (Nikkiso Co., Ltd.), the particle size, particle size distribution and average particle size of component (C) were measured.
The measurement sample was prepared by adding the target particles to a dispersion (dispersion solvent: water, dispersant: sodium hexametaphosphate (0.2% by mass)) and ultrasonically dispersing (80 W, 5 minutes).
The solvent refractive index was 1.333 and the particle refractive index was 1.57.
The particle size at an integrated value of 50% in the particle size distribution determined by the laser diffraction / scattering method was defined as the average particle size.

<Moisture content (water content)>
About 1 g of a sample was weighed and measured using a Karl Fischer moisture meter under the conditions of a heating temperature of 150 ° C. and a carrier gas dry nitrogen purge.
As a measurement sample, a compound pellet was used in the case of a resin composition, and in the case of a sheet, it was cut to be about 1 g.

<Na ₂ O content>
The content of Na ₂ O in component (C) was measured by fluorescent X-ray spectroscopy.

<Thermal conductivity>
Based on ASTM D5470, it measured by the stationary method. Specifically, using a resin material thermal resistance measuring device (manufactured by Hitachi, Ltd.), the measurement was performed under the conditions of a measurement temperature of 80 ° C. and a test piece thickness of 1.0 mm.

<Flexibility (hardness)>
Based on JIS K6253-3, the measured value after 15 seconds was recorded using durometer type A (JIS A hardness meter, manufactured by Kobunshi Keiki Co., Ltd.). A plurality of test pieces were measured so as to have a thickness of 6 mm.

<Tensile breaking elongation>
In accordance with JIS K7127, a strip-shaped test piece having a width of 10 mm in the MD direction and TD direction of the sheet was prepared and measured under the conditions of a distance between chucks of 115 mm and a tensile speed of 50 mm / min.

<Flame retardance>
The measurement was performed in accordance with UL94 (standard defined by Under Writers Laboratories Inc.) vertical combustion test.
The test piece was 130 mm long, 13 mm wide, and 1.0 mm thick. Specifically, after flame contact for 10 seconds, the combustion time from release of the flame to flame extinguishing was measured, and after flame extinction, the flame contacted again for 10 seconds, and the combustion time from flame release to flame extinction was measured. This was evaluated by one set of five (combustion time was measured 10 times in total). The maximum combustion time during 10 times, the total combustion time of 10 times, and the presence or absence of drip during combustion were evaluated. This result was determined based on the following criteria.
V-0: Maximum combustion time 10 seconds or less, total combustion time 50 seconds or less, no drip V-1: Maximum combustion time 30 seconds or less, total combustion time 250 seconds or less, no drip V-2: Maximum combustion time 30 seconds or less, total combustion time 250 seconds or less, with drip NG: not satisfying the above conditions

<Stability evaluation of raw material supply capacity>
The screw speed was adjusted so that the extrusion torque was 30 amperes on average with the equipment and conditions in [Sheet Production Method]. At this time, the number of screw rotations during a certain period of time was measured and used as a reference for stability of raw material supply capacity. It was evaluated that the raw material was stably supplied to the molding machine as the width of the screw rotation speed was smaller.

<Sheet workability evaluation>
The following evaluations were performed while adjusting the screw rotation speed so that the extrusion torque was 30 amperes on average with the equipment and conditions in [Sheet Production Method].
Discharge amount: The sheet extrusion mass for a fixed time was measured.
Torque fluctuation: The upper and lower limits of the torque fluctuation value during 30 minutes of extrusion were measured.

<Thickness accuracy>
The thickness was measured using a micrometer at a pitch of 50 mm for 3 m in the MD direction of the central portion of the sheet obtained with the equipment and conditions in [Sheet Production Method], and the maximum value and the minimum value were compared.

<Vibration absorption>
As shown in FIG. 1, two heat dissipating sheets 2 were attached between the lithium ion battery cells 3 (66) and the heat sink 1 to produce a battery module. The electrode 4 was attached to the upper part of the lithium ion battery.
The thickness of the heat dissipation sheet was 1.5 mm. An acceleration sensor was attached to the battery module, and it was further fixed to a vibration tester (produced by Index Co., LTD), and a vibration test was performed under conditions of a frequency of 40 Hz, an acceleration of 1.25 G, and a vibration time of 60 minutes.
The acceleration in the Z-axis direction by the acceleration sensor and the shape change of the heat dissipation sheet after the test were measured.
◯: The acceleration was suppressed by 20% or more compared to the state without the heat dissipation sheet, and the sheet was not torn.
(Triangle | delta): Although the acceleration was suppressed only less than 20% compared with the state without a heat radiating sheet, the sheet | seat was not torn.
X: The acceleration was suppressed to less than 20% as compared with the state without the heat dissipation sheet, and the sheet was torn.

[Examples 1 to 12], [Comparative Examples 1 to 5]
About Examples 1-12 and Comparative Examples 1-5, a resin composition and a sheet | seat are produced by the mixing | blending shown in Table 1 and Table 2, hardness, tensile breaking elongation, thermal conductivity, a flame retardance, raw material supply capability stability The sheet processability and thickness accuracy were evaluated.
Furthermore, vibration absorption when a sheet was sandwiched between battery modules was evaluated.
The results are shown in Tables 1 and 2.

  As is clear from Tables 1 and 2, the resin compositions and sheets of Examples 1 to 12 have thermal conductivity and flame retardancy, are flexible, have high thickness accuracy, and are stable raw materials during sheet production. It was confirmed that it has supply capability and vibration absorption.

  The resin composition of the present invention has industrial applicability as a heat conducting material for various electric / electronic components, semiconductor devices, display devices, communication devices, power devices and the like.

1 heat sink 2 heat dissipation sheet 3 cell 4 electrode

Claims (14)

(A) 2-20% by mass of a copolymer containing a conjugated diene unit and a vinyl aromatic compound unit and / or a hydrogenated product thereof,
(B) 2-20% by mass of a rubber softener,
(C) 70 to 95% by mass of a thermally conductive filler,
(D) 0.1 to 3% by mass of at least one additive selected from the group consisting of silica, talc, calcium carbonate, barium sulfate, kaolinite, apatite, diatomaceous earth, zeolite, and mica;
A resin composition comprising:   The resin composition of Claim 1 whose average particle diameter of the said (C) heat conductive filler is 10-150 micrometers.   The said (C) heat conductive filler has two or more different maximum values in the particle size distribution, and the difference of the particle diameter which shows each maximum value is 50 micrometers or more. Resin composition. As the (C) thermally conductive filler,
(CI) a first thermally conductive filler having an average particle size of 60 μm or more and 150 μm or less;
(C-II) The resin composition as described in any one of Claims 1 thru | or 3 containing the 2nd heat conductive filler whose average particle diameter is 5 micrometers or more and 60 micrometers or less.   The resin according to claim 4, wherein a mass ratio ((CI) / (C-II)) of the (CI) component to the (C-II) component is 100/1 to 100/170. Composition. Wherein (C) Na ₂ O concentration in the thermally conductive filler is 1.00% by mass or less exceed 0.20 wt%, the resin composition according to any one of claims 1 to 5. The content of the vinyl aromatic compound unit in the copolymer (A) and / or hydrogenated product thereof is less than 30% by mass,
The mass ratio ((A) / (B)) of (A) copolymer and / or hydrogenated product thereof to (B) rubber softener is 35/65 to 60/40. The resin composition as described in any one of these.   The (C) thermally conductive filler is at least one selected from the group consisting of a metal nitride not containing silicon, a metal oxide not containing silicon, and a metal hydroxide not containing silicon. The resin composition as described in any one of thru | or 7.   The resin composition according to any one of claims 1 to 8, wherein the heat conductive filler (C) is aluminum hydroxide or alumina.   The resin composition according to any one of claims 1 to 9, wherein the additive (D) is silica or talc.   (E) The resin composition as described in any one of Claims 1 thru | or 10 which further contains 0.01-2 mass% of plasticizers.   The resin composition according to any one of claims 1 to 11, wherein the durometer type A hardness is less than 60 in accordance with JIS K6253-3.   A sheet comprising the resin composition according to any one of claims 1 to 12 and having a thickness of 0.1 to 10 mm.   The sheet according to claim 13, wherein the water content is 200 ppm or less.