WO2020066766A1 - Thermoconductive putty composition, and thermoconductive sheet and heat dissipation structure in which same is used - Google Patents

Abstract

This thermoconductive putty composition contains: a base polymer that includes, as a main component, a liquid polymer having a hydroxy group; and a thermoconductive filler. The thermoconductive filler content is 500-3000 parts by mass per 100 parts by mass of the base polymer.

Description

Thermal conductive putty composition, and thermal conductive sheet and heat dissipation structure using the same

The present invention relates to a thermally conductive putty composition, and a thermally conductive sheet and a heat dissipation structure using the same.

With the increase in the energy of secondary battery modules and the density of elements on electronic and electric circuit boards, the amount of heat generated from heat-generating articles such as secondary battery modules, electronic and electric circuit boards, etc. As means for efficiently dissipating heat, a heat conductive sheet is used.

On the other hand, for secondary battery modules and electronic / electric circuit boards used in cold regions, etc., it is necessary to warm up the secondary battery modules and electronic / electric circuit boards before operating them. In this case, it is necessary to efficiently supply heat from the outside (such as a heater) to the secondary battery module and the electronic / electric circuit board.

Under these circumstances, in recent years, there has been a development to improve the flexibility of the heat conductive sheet in order to increase the contact area with the surface of the secondary battery module or the electronic / electric circuit board to increase the heat conductivity (heat dissipation, heat-generating property). (For example, Patent Documents 1 and 2).

In addition, in order to eliminate unnecessary conduction to the electronic device via the heat conductive sheet, an insulating layer is provided between the electronic device and the heat conductive sheet. For example, Patent Documents 3 and 4 disclose a composite sheet obtained by laminating insulating sheets on both sides of a heat conductive sheet and sealing the heat conductive sheet with the insulating sheets sandwiched therebetween. It is disclosed to be used as a conductive member.

JP-A-2017-141443 Japanese Patent Application Laid-Open No. 2017-069341 International Publication No. WO 2017/159527 WO 2017/159528

The present invention is a thermally conductive putty composition containing a base polymer containing a liquid polymer having a hydroxy group as a main component and a thermally conductive filler, wherein the content of the thermally conductive filler is 100% by mass of the base polymer. Parts by mass to 500 parts by mass or more and 3000 parts by mass or less.

The present invention is a heat conductive sheet obtained by molding the heat conductive putty composition of the present invention into a sheet. Further, the present invention is a heat dissipating structure in which the heat conductive sheet of the present invention is stuck on the surface of a heat generating article.

FIG. 2 is a perspective view of the secondary battery modules of Embodiments 1 and 2. FIG. 2 is an exploded perspective view of the secondary battery modules of Embodiments 1 and 2. It is II-II sectional drawing in FIG. 1A. It is III-III sectional drawing in FIG. 1A. It is sectional drawing of the heat conductive laminated structure which concerns on Embodiment 3. FIG. 9 is a cross-sectional view of a heat dissipation structure having a heat conductive laminated structure according to a third embodiment.

Hereinafter, embodiments will be described in detail.

(Embodiment 1)
The thermally conductive putty composition according to the first embodiment includes a non-crosslinked base polymer serving as a matrix containing a liquid polymer having a hydroxy group (hereinafter, referred to as “liquid polymer A”) as a main component, and a base polymer of the matrix. And a thermally conductive filler dispersed therein. And the content of a heat conductive filler is 500 to 3000 parts by mass based on 100 parts by mass of the base polymer.

According to such a thermally conductive putty composition according to Embodiment 1, since the base polymer contains the liquid polymer A as a main component, it is possible to contain a large amount of the thermally conductive filler while maintaining the putty properties, When the content of the heat conductive filler is not less than 500 parts by mass and not more than 3000 parts by mass with respect to 100 parts by mass of the base polymer, it is deformed following the surface shape of the heat-generating article and has high heat conductivity (heat dissipation). Properties, heat-generating properties). Here, the “liquid polymer” in the present application refers to a polymer that is liquid at normal temperature and normal pressure (25 ° C., 1 atm).

The base polymer contains the liquid polymer A as a main component. Therefore, the content of the liquid polymer A in the base polymer is 50% by mass or more, preferably 80% by mass or more, more preferably 90% by mass or more, and most preferably 100% by mass. The base polymer may contain a liquid polymer having no hydroxy group other than the liquid polymer A (hereinafter, referred to as “liquid polymer B”) as an auxiliary component, or may contain other polymers. .

Although the liquid polymer A has a hydroxy group, from the viewpoint of obtaining excellent shape followability and high thermal conductivity of the thermally conductive putty composition, the basic skeleton of the hydrocarbon may be modified with a hydroxy group. preferable. The basic skeleton of the hydrocarbon is not particularly limited, and examples thereof include a saturated hydrocarbon, an unsaturated hydrocarbon, an alicyclic hydrocarbon, and an aromatic hydrocarbon. Specific examples include polybutadiene; polyisoprene; and polyolefins such as polyethylene, polypropylene, and ethylene-propylene copolymer. The basic skeleton of the hydrocarbon preferably contains one or more of these.

The hydroxy group content in the liquid polymer A is preferably from 0.3 mol / kg to 3 mol / kg, more preferably 0.5 mol, from the viewpoint of obtaining excellent shape followability and high thermal conductivity of the thermally conductive putty composition. / Kg or more and 2 mol / kg or less. The hydroxy group content in the liquid polymer A is calculated from the following formula (1) based on the hydroxyl valency measured according to JIS K1557-1: 2007.
Hydroxy group content (mol / kg) = hydroxyl valence (mgKOH / g) / A ... (1)
(A: molecular weight of KOH)

The viscosity of the liquid polymer A at 30 ° C. is preferably 0.5 Pa · s or more and 100 Pa · s or less, more preferably 1 Pa or less, from the viewpoint of obtaining excellent shape followability and high thermal conductivity of the thermally conductive putty composition. 0.0 Pa · s or more and 90 Pa · s or less. The viscosity of the liquid polymer A is measured according to JIS K2283: 2000.

数 The number average molecular weight of the liquid polymer A is preferably 800 or more and 4000 or less, more preferably 1000 or more and 3500 or less, from the viewpoint of obtaining excellent shape followability and high thermal conductivity of the thermally conductive putty composition. The number average molecular weight of the liquid polymer A is measured according to ASTM D2503.

The hydroxy group may modify the terminal of the hydrocarbon basic skeleton, may modify the middle part of the hydrocarbon basic skeleton, and may modify both the terminal and the intermediate part of the hydrocarbon basic skeleton. May be. The hydroxy group preferably modifies at least the terminal of the basic skeleton of the hydrocarbon from the viewpoint of obtaining excellent shape followability and high thermal conductivity of the thermally conductive putty composition, and the terminal of the basic skeleton of the hydrocarbon is preferably used. It is more preferred that both the intermediate portion and the intermediate portion are modified.

Examples of the commercially available liquid polymer A in which the terminal of the basic skeleton of the hydrocarbon is modified with a hydroxy group include, for example, G series and GI series of NISSO-PB manufactured by Nippon Soda Co., Ltd., and polytail manufactured by Mitsubishi Chemical Corporation. Examples of the commercially available liquid polymer A in which both the terminal and the intermediate part of the basic skeleton of the hydrocarbon are modified with hydroxy groups include, for example, Poly 出 bd, Poly 、 ip, EPOL and the like manufactured by Idemitsu Kosan Co., Ltd.

As the liquid polymer B, a polymer having a hydrocarbon as a basic skeleton is preferable, and examples thereof include a naphthene polymer, a paraffin polymer, and an aromatic polymer. The liquid polymer B preferably contains one or more of these, and from the viewpoint of obtaining excellent shape followability and high thermal conductivity of the thermally conductive putty composition, a paraffin-based polymer and / or an aroma. It is more preferable to include a system polymer.

Examples of commercially available naphthenic polymers include SNH series manufactured by Sankyo Yuka Kogyo Co., Ltd., and SUNTHENE series manufactured by Nippon Sun Oil Co., Ltd. Examples of commercially available paraffin-based polymers include, for example, NA Solvent manufactured by NOF Corporation, PW series manufactured by Idemitsu Kosan, SUNPAR series manufactured by Nippon Sun Oil Co., Ltd., B series and BI series of NISSO-PB manufactured by Nippon Soda, and NOF Corporation Nippon Oil Polybutene Series, JXTG Energy Corporation Nisseki Polybutene Series, and the like. Commercially available aromatic polymers include, for example, JSO AROMA 790.

液状 The content of the liquid polymer B in the base polymer is 50% by mass or less, preferably 20% by mass or less, more preferably 10% by mass or less.

Examples of the heat conductive filler include metal oxides such as aluminum oxide, magnesium oxide, beryllium oxide, zinc oxide, silicon oxide, and titanium oxide; metal hydroxides such as aluminum hydroxide, aluminum nitride, boron nitride, and silicon nitride. Metal such as gold, silver, copper, aluminum, tungsten, titanium, nickel, iron and alloys of two or more thereof; carbon compounds such as graphite (graphite), carbon fiber, fullerene, graphene and carbon nanotube And the like. The heat conductive filler preferably contains one or more of these, and more preferably contains one or more of metal oxides, metal hydroxides, and metal nitrides, More preferably, it contains aluminum oxide. The shape of the heat conductive filler is preferably spherical or disc-shaped from the viewpoint of obtaining excellent shape followability and high heat conductivity of the heat conductive putty composition. The spherical heat conductive filler may have an organic functional group such as a vinyl group, an epoxy group, an amino group, a methacryl group, an isocyanate group, and a mercapto group on the surface by a surface treatment with a silane coupling agent or the like. This organic functional group preferably contains one or more of these, and more preferably contains one or more of a vinyl group, an amino group, and a methacryl group.

The average particle diameter (d ₅₀ ) of the heat conductive filler is preferably 0.5 μm or more and 100 μm or less, more preferably 3 μm or more and 80 μm, from the viewpoint of obtaining excellent shape followability and high heat conductivity of the heat conductive putty composition. The thickness is more preferably 5 μm or more and 60 μm or less. This average particle diameter (d ₅₀ ) is measured by the Coulter counter method. From the same viewpoint, the particle size distribution of the heat conductive filler preferably has a plurality of peaks. Therefore, it is preferable that the heat conductive filler include a plurality of types having different average particle diameters (d ₅₀ ). When the heat conductive filler contains two kinds having different average particle diameters (d ₅₀ ), for example, the peak on the small diameter side is in the range of 0.3 μm to 10 μm, and the peak on the large diameter side is 20 μm to 100 μm. Is preferred. When the heat conductive filler contains three kinds having different average particle diameters (d ₅₀ ), the peak on the small diameter side is in the range of 0.1 μm or more and 1 μm or less, the peak of the intermediate diameter is in the range of 1 μm or more and 60 μm or less, it is preferred that the peak of the large diameter side is in 10μm or 100μm or less (larger diameter _{d 50> d} 50 of intermediate diameter).

Although the content of the heat conductive filler in the heat conductive putty composition according to Embodiment 1 is 500 parts by mass or more and 3000 parts by mass or less with respect to 100 parts by mass of the base polymer, the excellent shape of the heat conductive putty composition From the viewpoint of obtaining followability and high thermal conductivity, preferably 800 parts by mass or more and 2700 parts by mass or less, more preferably 1000 parts by mass or more and 2600 parts by mass or less, still more preferably 1000 parts by mass or more and 2500 parts by mass or less, still more preferably Is from 1200 parts by mass to 2400 parts by mass.

熱 The thermally conductive putty composition according to Embodiment 1 may further contain a viscosity modifier such as bentonite.

According to JIS H7903: 2008, the thermal conductivity of the thermally conductive putty composition according to Embodiment 1 measured at a measurement temperature of 33 ° C. (unidirectional heat flow steady state comparison method (SCHF)) is preferably 2 W / m · K or more, more preferably 5 W / m · K or more.

According to JIS A5752: 1994 as an index of the hardness of the thermally conductive putty composition according to Embodiment 1, the softness measured at a measurement temperature of 23 ± 3 ° C is preferably 40 or more, more preferably 50 or more. It is.

With respect to the heat conductive putty composition according to Embodiment 1, at a measurement temperature of 23 ± 3 ° C., a 1 cm square piece having a thickness of 2.0 mm was compressed to a thickness of 0.5 mm with a change in compression load of 15 N / min ( The load (hereinafter referred to as “compression reaction force”) required to perform the compression (75% compression) is preferably 90 N or less, more preferably 70 N or less.

The heat-dissipating putty composition according to the first embodiment deforms following the surface shape of the heat-generating article, and has a high heat conductivity (heat-dissipating property, heat-generating property). The value obtained by multiplying the above-described value of the thermal conductivity by the above-described value of the softness can be evaluated as an index. The numerical value is preferably 350 or more and 2000 or less, more preferably 1000 or more and 1800 or less.

The heat conductive putty composition according to the first embodiment is kneaded with a base polymer containing the liquid polymer A and a heat conductive filler by a kneading machine such as a Banbury, a kneader, a planetary mixer, and a rotation revolution mixer. It can be manufactured by the following.

From the heat conductive putty composition according to the first embodiment, a heat conductive sheet can be produced by molding the composition into a sheet by a known molding method such as extrusion molding by an extruder or press molding by a press machine. it can. Such a heat conductive sheet is cut out to an appropriate size according to the heat-generating article, is attached to a desired heat-generating article surface, and follows a surface shape of the heat-generating article when an appropriate load is applied. And is in contact with the surface of the heat-generating article over a wide area to exhibit high heat dissipation (or heat-generating property). The thickness of the heat conductive sheet is, for example, 0.1 mm or more and 20 mm or less.

FIGS. 1A and 1B show a lithium ion secondary battery module 10 as an example of a heat dissipation structure. The lithium ion secondary battery module 10 includes a module main body (heat-generating article) 11 and first and second heat conductive sheets 12 in which the heat conductive putty composition according to the first embodiment is formed into a sheet. . The module main body 11 has a plurality of lithium ion secondary batteries 111 and a pair of battery holders 112.

The plurality of lithium ion secondary batteries 111 are each formed in a columnar shape, and are provided in parallel at intervals. Each of the pair of battery holders 112 is formed in a plate shape, and one is provided at one end of the plurality of lithium ion secondary batteries 111 and the other is provided at the other end thereof. Each of the battery holders 112 has a bottomed cylindrical hole-shaped battery holding portion 112a formed so as to correspond to each of the plurality of lithium ion secondary batteries 111. The lithium ion secondary batteries 111 are provided in the battery holding portions 112a. Are configured to be fitted and held. A round hole 112b is formed at the center of the bottom surface of each battery holder 112a, and an electric wire is connected to the lithium ion secondary battery 111 through the round hole 112b.

{Circle around (1)} The first heat conductive sheet 12 is provided so as to cover the uneven surface outside the plurality of lithium ion secondary batteries 111 provided in parallel. When the first heat conductive sheet 12 is pressed from the outside at the time of attachment, as shown in FIG. 2, the first heat conductive sheet 12 is deformed to follow the surface shape of the plurality of lithium ion secondary batteries 111 and the inside of the module is deformed. It flows between the lithium ion secondary batteries 111 adjacent to each other, and thereby comes into contact with the lithium ion secondary batteries 111 in a wide area, so that high heat dissipation (or heat supply) can be obtained.

{Circle around (2)} The second heat conductive sheet 12 is provided so as to be stuck on the outer uneven surface of each of the pair of battery holders 112. When the second heat conductive sheet 12 is pressed from the outside at the time of attachment, the second heat conductive sheet 12 deforms to follow the surface shape of the battery holder 112 and flows into the round hole 112b as shown in FIG. By contacting the ion secondary battery 111, high heat dissipation (or heat application) can be obtained.

In the first embodiment, the lithium-ion secondary battery module 10 is shown as the heat dissipation structure. However, the present invention is not limited to this, and may be an electronic / electric circuit board or the like. In the case of an electronic / electric circuit board, for example, the above-mentioned uneven surface on the element side where elements such as resistors, capacitors, semiconductor elements, and LEDs and wiring are provided at a high density, and the uneven surface on the back side where many traces of soldering are provided By attaching the heat conductive sheet, high heat dissipation (or heat application) can be obtained.

[Example 1]
(Thermal conductive putty composition)
The following thermally conductive putty compositions of Examples 1-1 to 1-6 and Comparative Examples 1-1 to 1-2 were produced. Each configuration is also shown in Table 1-1.

<Example 1-1>
Liquid polymer (Poly bd R-45HT manufactured by Idemitsu Kosan Co., Ltd., hydroxy group content: 0.83 mol / kg, viscosity (30 ° C.): 5 Pa · s, number average molecular weight: 2800) and a liquid polymer of polybutadiene not modified with a hydroxy group (HV-300 manufactured by JXTG Energy, viscosity (30 ° C.): 23.3 Pa · s, number average molecular weight: 1400) at a ratio of 1: 1. the mixed polymer blend of non-crosslinked base polymer, relative to the 100 parts by mass of the base polymer, as the heat conduction filler, spherical aluminum oxide (spherical alumina: Arunabizu CB-A70, manufactured by Showa Denko KK, average particle size (d ₅₀ ): 71 μm, number of particle size distribution peaks: 1) 1540 parts by mass, spherical aluminum oxide ( Spherical alumina: Alumina beads CB-P40, manufactured by Showa Denko KK, average particle diameter (d ₅₀ ): 40 μm, number of particle size distribution peaks: 1) 330 parts by mass, and spherical aluminum oxide (polyhedral spherical advanced alumina AA-04 Sumitomo Chemical Co., Ltd.) A thermal conductive putty composition prepared by mixing and kneading with a kneader a mixture of 330 parts by mass of an average particle size (d ₅₀ ): 0.5 μm, the number of particle size distribution peaks: 1) was prepared in Example 1-1. And In addition, the total compounding amount of the heat conductive filler is 2200 parts by mass based on 100 parts by mass of the base polymer.

<Example 1-2>
Liquid polymer (Poly bd R-45HT manufactured by Idemitsu Kosan Co., Ltd., hydroxy group content: 0.83 mol / kg, viscosity (30 ° C.): 5 Pa · s, number average molecular weight: 2800) as a base polymer, and a disc-shaped aluminum oxide (round alumina: AS-40 manufactured by Showa Denko KK, average particle size (d ₅₀ ): 12 μm) as a heat conductive filler with respect to 100 parts by mass of the base polymer. 1,400 parts by mass of titanium oxide (FR-22, manufactured by Furukawa Chemicals Co., Ltd., average particle diameter (d ₅₀ ): 12 μm, number of peaks of particle size distribution: 1), and 150 parts by mass of a titanium oxide. The heat conductive putty composition prepared by kneading was used as Example 1-2. In addition, the total compounding amount of the heat conductive filler is 1550 parts by mass with respect to 100 parts by mass of the base polymer.

<Example 1-3>
A heat conductive putty composition prepared in the same manner as in Example 1-2 except that 1700 parts by weight of spherical aluminum oxide was blended as a heat conductive filler with respect to 100 parts by weight of the base polymer, was prepared in Example 1-3. And

<Example 1-4>
The heat conductive putty composition prepared in the same manner as in Example 1-3 except that the blending amount of the spherical aluminum oxide of the heat conductive filler was 1300 parts by mass with respect to 100 parts by mass of the base polymer, It was set to 1-4.

<Example 1-5>
As the base polymer, a liquid polymer (Poly ip, manufactured by Idemitsu Kosan Co., Ltd., hydroxy group content: 0.83 mol / kg, viscosity (30 ° C.): 7.5 Pa · s, polyisoprene having a terminal and an intermediate portion modified with a hydroxy group) A heat conductive putty composition prepared in the same manner as in Example 1-1 except that only the number average molecular weight: 2500) was used was referred to as Example 1-5.

<Example 1-6>
As a base polymer, a liquid polymer in which the terminal and intermediate portions of a polyolefin are modified with a hydroxy group (EP @ L, manufactured by Idemitsu Kosan Co., Ltd., hydroxy group content: 0.9 mol / kg, viscosity (30 ° C.): 75 Pa · s, number average molecular weight: A heat conductive putty composition prepared in the same manner as in Example 1-1 except that only 2500) was used was referred to as Example 1-6.

<Comparative Example 1-1>
A disc-shaped aluminum oxide (round alumina: AS-40, manufactured by Showa Denko KK, average particle diameter (d ₅₀ ): 12 μm, number of particle size distribution peaks: 2) was used as a heat conductive filler, and the compounding amount was used as a base. A thermally conductive putty composition prepared in the same manner as in Example 1-1 except that the amount was 450 parts by mass with respect to 100 parts by mass of the polymer was designated as Comparative Example 1-1.

<Comparative Example 1-2>
A disc-shaped aluminum oxide (round alumina: AS-40, manufactured by Showa Denko KK, average particle diameter (d ₅₀ ): 12 μm, number of particle size distribution peaks: 2) was used as a heat conductive filler, and the compounding amount was used as a base. A thermally conductive putty composition prepared in the same manner as in Example 1-1 except that the amount was 3100 parts by mass relative to 100 parts by mass of the polymer was designated as Comparative Example 1-2.

(Test method)
<Thermal conductivity>
The thermal conductivity of each of Examples 1-1 to 1-6 and Comparative Examples 1-1 and 1-2 was measured by a one-way steady-state heat flow comparison method (SCHF) at a measurement temperature of 33 ° C. in accordance with JIS H7903: 2008. It was measured.

<Softness>
For each of Examples 1-1 to 1-6 and Comparative Examples 1-1 and 1-2, the softness was measured as a softness index at a measurement temperature of 23 ± 3 ° C. in accordance with JIS A5752: 1994.

<Compression reaction force>
For each of Examples 1-1 to 1-6 and Comparative Examples 1-1 to 1-2, a 2.0 cm thick 1 cm square test piece was compressed to a thickness of 0.5 mm (75% compression). The required load (measuring temperature: 23 ± 3 ° C.) was measured.

(Test results)
The test results are shown in Table 1-2. According to Table 1-2, Examples 1-1 to 1-6 have higher thermal conductivity than Comparative Examples 1-1 to 1-2, and have excellent shape following properties since they are sufficiently soft. Therefore, it can be seen that the total heat dissipation performance is excellent.

(Embodiment 2)
The thermally conductive putty composition according to Embodiment 2 contains a liquid polymer, aluminum hydroxide, and bentonite. Aluminum hydroxide and bentonite are dispersed in the liquid polymer.

Examples of the liquid polymer include liquid polyolefins such as liquid polybutadiene, liquid polyisoprene, liquid polybutene, and liquid ethylene propylene copolymer; liquid silicone; liquid acrylic; liquid urethane, and the like. The liquid polymer preferably contains one or more of these, and more preferably contains a liquid polyolefin. The liquid polymer preferably does not contain a halogen element in the molecule from the viewpoint of preventing generation of halogen gas during combustion.

The liquid polymer preferably contains liquid polybutadiene, and may be composed of only liquid polybutadiene. Further, the liquid polymer preferably contains a mixture of relatively low-viscosity liquid polybutadiene and high-viscosity liquid polybutene, and may be composed of only a mixture of those liquid polybutadiene and liquid polybutene. When the liquid polymer contains a mixture of liquid polybutadiene and liquid polybutene, the mass ratio of the content of the liquid polybutadiene to the content of the liquid polybutene (the content of the liquid polybutadiene / the content of the liquid polybutene) increases the flame retardancy. From the viewpoint of imparting adhesiveness and enhancing the adhesion to the article, the ratio is preferably 20/80 or more and 99/1 or less, more preferably 30/70 or more and 60/40 or less.

As in the first embodiment, the liquid polymer may include the liquid polymer A having a hydroxy group, or the liquid polymer A and the liquid polymer B having no hydroxy group.

ア ル ミ ニ ウ ム Aluminum hydroxide is a particulate material that imparts flame retardancy to the thermally conductive putty composition. The oxygen index of the flame retardancy index of the thermally conductive putty composition according to Embodiment 2 is preferably 50 or more, more preferably 65 or more. The average particle size of the aluminum hydroxide is preferably 0.5 μm or more and 100 μm or less, more preferably 15 μm or more and 60 μm or less, from the viewpoint of enhancing the softness as well as the thermal conductivity.

粒度 The particle size distribution of the aluminum hydroxide preferably has a plurality of peaks from the viewpoint of enhancing thermal conductivity, dispersibility in a liquid polymer, and flame retardancy. Therefore, the aluminum hydroxide preferably contains a plurality of types having different average particle sizes. Specifically, for example, aluminum hydroxide has an average particle diameter of aluminum hydroxide A having an average particle diameter of greater than 10 μm and 100 μm or less and aluminum hydroxide B having an average particle diameter of 10 μm or less with respect to 100 parts by mass of aluminum hydroxide A. And containing aluminum hydroxide B in a proportion of 50 parts by mass or more and 200 parts by mass or less, and having a particle size distribution having a first peak having an average particle size of more than 10 μm and 100 μm or less and a second peak having an average particle size of 10 μm or less. It may be. Aluminum hydroxide is aluminum hydroxide X having an average particle size of 0.5 μm or more and less than 10 μm, aluminum hydroxide Y having an average particle size of 10 μm or more and less than 30 μm, and aluminum hydroxide having an average particle size of 30 μm or more and 100 μm or less. Two or more kinds of Z are contained in aluminum hydroxide Y and 100 parts by mass of aluminum hydroxide at a ratio of 50 parts by mass or more and 200 parts by mass or less of aluminum hydroxide X, and the particle size distribution has an average particle size of 30 μm or more and 100 μm or less. It may have one peak and a second peak having an average particle size of 0.5 μm or more and less than 30 μm.

The content of aluminum hydroxide in the thermally conductive putty composition according to Embodiment 2 is 150 parts by mass or more and 1000 parts by mass or less with respect to 100 parts by mass of the liquid polymer, from the viewpoint of enhancing workability with thermal conductivity. It is preferably from 400 to 700 parts by mass, more preferably from 450 to 650 parts by mass.

The thermally conductive putty composition according to Embodiment 2 may contain a thermally conductive filler other than aluminum hydroxide.

Bentonite is a type of montmorillonite mainly composed of SiO ₂ and Al ₂ O ₃ (for example, montmorillonite, magnesia montmorillonite, tetmontmorillonite, tetmagnesian montmorillonite, beidellite, aluminian beidellite, nontron) Stone, aluminian nontronite, saboite, aluminian saboite, hectorite, sauconite, bolconite, etc.). The bentonite may include protein stone, buffalo stone, fluorite, volcanic glass and the like in addition to montmorillonite. In addition, from the viewpoint of enhancing dispersibility in a liquid polymer, the bentonite preferably contains organic bentonite that has been subjected to an organic treatment by replacing an exchangeable base such as Na, Ca, or Mg with an organic amine.

The content of bentonite in the thermally conductive putty composition according to Embodiment 2 is preferably 5 parts by mass or more and 20 parts by mass or less with respect to 100 parts by mass of the liquid polymer, from the viewpoint of increasing the softness along with the thermal conductivity. Is from 7 to 15 parts by mass, more preferably from 9 to 13 parts by mass.

According to JIS H7903: 2008, the thermal conductivity of the thermally conductive putty composition according to Embodiment 2 measured at a measurement temperature of 33 ° C. (unidirectional heat flow steady state comparison method (SCHF)) is preferably 0.5 W / m · K or more, more preferably 2.0 W / m · K or more, still more preferably 3.0 W / m · K or more.

According to JIS A5752: 1994 as an index of the softness of the thermally conductive putty composition according to Embodiment 2, the penetration amount measured at a measurement temperature of 23 ± 3 ° C is preferably 50 mm or more, more preferably 75 mm. And preferably 110 mm or less.

The heat conductive putty composition according to the second embodiment is obtained by charging a liquid polymer, aluminum hydroxide, and bentonite into a kneader such as a kneader, and controlling the kneading temperature to 20 ° C or more and 80 ° C or less. Kneading with a kneading time of 30 minutes or more and 60 minutes or less.

According to the heat conductive putty composition according to Embodiment 2 having the above configuration, the liquid polymer, aluminum hydroxide, and bentonite are contained, and the content of aluminum hydroxide is 150 per 100 parts by mass of the liquid polymer. Not less than 5 parts by mass and not more than 1000 parts by mass, and the content of bentonite is not less than 5 parts by mass and not more than 20 parts by mass with respect to 100 parts by mass of the liquid polymer. As a result, the article comes into contact with the article over a wide area, and thereby a high heat dissipation (or heat giving property) can be obtained. In addition, since aluminum hydroxide also functions as a flame retardant, the thermally conductive putty composition according to Embodiment 2 can obtain high non-halo flame retardancy (oxygen index of 65 or more).

From the thermally conductive putty composition according to Embodiment 2, it is possible to produce a thermally conductive sheet by molding the same into a sheet by a known molding method such as extrusion molding by an extruder or press molding by a press machine. it can. Such a heat conductive sheet is cut out to an appropriate size according to the article, attached to a desired article surface and given an appropriate load, and deformed to follow the surface shape of the article, It exhibits high heat dissipation (or heat-generating property) by contacting the surface of the article over a wide area. The thickness of the heat conductive sheet is preferably 2 mm or more, more preferably 3 mm or more, preferably 20 mm or less, more preferably 10 mm or less.

物品 Here, examples of the article include a secondary battery module and an electronic / electric circuit board.

二 A secondary battery module 10 using the thermally conductive putty composition according to Embodiment 2 will be described with reference to FIGS. 1A and 1B, FIG. 2, and FIG.

As shown in FIGS. 1A and 1B, the secondary battery module 10 includes a module main body 11 and first and second heat conductive sheets 12 formed by molding the heat conductive putty composition according to the second embodiment into sheets. And The module main body 11 includes a plurality of secondary batteries 111 and a pair of battery holders 112.

The plurality of secondary batteries 111 are each formed in a columnar shape, and are provided in parallel at intervals. Each of the pair of battery holders 112 is formed in a plate shape, and one is provided on one end side of the plurality of secondary batteries 111 and the other is provided on the other end side thereof. Each battery holder 112 has a bottomed cylindrical hole-shaped battery holding portion 112a formed so as to correspond to each of the plurality of secondary batteries 111, and the battery holding portion 112a is provided with an end of the secondary battery 111. It is configured to be fitted and held. A round hole 112b is formed at the center of the bottom surface of each battery holder 112a, and an electric wire is connected to the secondary battery 111 through the round hole 112b.

{Circle around (1)} The first heat conductive sheet 12 is provided so as to cover the uneven surface outside the plurality of secondary batteries 111 provided in parallel. When the first heat conductive sheet 12 is pressed from the outside at the time of attachment, as shown in FIG. 2, the first heat conductive sheet 12 is deformed to follow the surface shape of the plurality of secondary batteries 111 and mutually deforms inside the module. It flows between the adjacent secondary batteries 111, and thereby comes into contact with the secondary batteries 111 in a wide area, so that high heat dissipation (or heat supply) can be obtained.

{Circle around (2)} The second heat conductive sheet 12 is provided so as to be stuck on the outer uneven surface of each of the pair of battery holders 112. When the second heat conductive sheet 12 is pressed from the outside at the time of attachment, the second heat conductive sheet 12 deforms to follow the surface shape of the battery holder 112 and flows into the round hole 112b as shown in FIG. By contacting the next battery 111, high heat dissipation (or heat-giving property) can be obtained.

As the uneven surface of the electronic / electric circuit board, for example, an element side surface on which elements such as resistors, capacitors, semiconductor elements, LEDs, and wiring are provided at a high density, and a back side surface on which a large number of traces of soldering are provided. Is mentioned. By adhering the heat conductive sheet on the uneven surface of such an electronic / electric circuit board, high heat dissipation (or heat application) can be obtained.

In the second embodiment, the following invention is disclosed.

<1> A liquid polymer, aluminum hydroxide, and bentonite are contained, and the content of the aluminum hydroxide is 150 parts by mass or more and 1000 parts by mass or less with respect to 100 parts by mass of the liquid polymer, and A thermally conductive putty composition having a content of 5 parts by mass or more and 20 parts by mass or less based on 100 parts by mass of the liquid polymer.

<2> The thermally conductive putty composition according to <1>, wherein the liquid polymer includes liquid polybutadiene or a mixture of liquid polybutadiene and liquid polybutene.

<3> The thermally conductive putty composition according to <1> or <2>, wherein the average particle size of the aluminum hydroxide is 0.5 μm or more and 100 μm or less.

<4> The thermally conductive putty composition according to any one of <1> to <3>, wherein the particle size distribution of the aluminum hydroxide has a plurality of peaks.

<5> The heat conductive putty composition according to any one of <1> to <4>, wherein the bentonite contains an organic bentonite that has been subjected to an organic treatment by replacing an exchangeable base with an organic amine. Conductive putty composition.

<6> A heat conductive sheet obtained by molding the heat conductive putty composition according to any one of <1> to <5> into a sheet.

<7> A battery module having the heat conductive sheet according to <6>.

[Example 2]
(Thermal conductive putty composition)
The following thermally conductive putty compositions of Examples 2-1 to 2-7 and Comparative Examples 2-1 to 2-2 were produced. Each configuration is also shown in Table 2-1.

<Example 2-1>
A mixture of 50 parts by mass of liquid polybutadiene and 50 parts by mass of liquid butene was used as a liquid polymer. With respect to 100 parts by mass of the liquid polymer, 170 parts by mass of aluminum hydroxide having an average particle diameter of 8 μm and 170 parts by mass of aluminum hydroxide were used. A mixture of 170 parts by mass of aluminum hydroxide Y having a diameter of 27 μm and 110 parts by mass of aluminum hydroxide Z having an average particle size of 55 μm, and 11 parts by mass of an organic bentonite that has been subjected to an organic treatment by replacing an exchangeable base with an organic amine is used. A heat conductive putty composition prepared by mixing and kneading with a kneader having a capacity of 2 L and kneading with a kneading time of 40 minutes while controlling the kneading temperature at 20 ° C. to 80 ° C. was prepared in Example 2-1. And

<Example 2-2>
A thermally conductive putty composition prepared in the same manner as in Example 2-1 except that aluminum hydroxide Z was compounded in an amount of 310 parts by mass with respect to 100 parts by mass of the liquid polymer was designated as Example 2-2.

<Example 2-3>
A thermally conductive putty composition prepared in the same manner as in Example 2-1 except that a mixture of 30 parts by mass of liquid polybutadiene and 70 parts by mass of liquid butene was used as a liquid polymer was designated as Example 2-3.

<Example 2-4>
A thermally conductive putty composition prepared in the same manner as in Example 2-1 except that a mixture of 70 parts by mass of liquid polybutadiene and 30 parts by mass of liquid butene was used as a liquid polymer was designated as Example 2-4.

<Example 2-5>
A thermally conductive putty composition prepared in the same manner as in Example 2-1 except that 100 parts by mass of liquid polybutadiene was used as a liquid polymer was used as Example 2-5.

<Example 2-6>
A thermally conductive putty composition prepared in the same manner as in Example 2-2 except that 100 parts by mass of liquid polybutadiene was used as a liquid polymer was used as Example 2-6.

<Example 2-7>
A heat-conductive putty composition prepared in the same manner as in Example 2-5 except that only aluminum hydroxide Z was blended in an amount of 500 parts by mass with respect to 100 parts by mass of the liquid polymer as the aluminum hydroxide, was used. 7 was set.

<Comparative Example 2-1>
A thermally conductive putty composition prepared in the same manner as in Example 2-1 except that bentonite was not blended was used as Comparative Example 2-1.

<Comparative Example 2-2>
A thermally conductive putty composition prepared in the same manner as in Example 2-1 except that aluminum hydroxide was not blended was used as Comparative Example 2-2.

(Test method)
<Workability>
Each of Examples 2-1 to 2-7 and Comparative examples 2-1 to 2-2 was extruded by an extruder, and a case where a heat conductive sheet having a thickness of 3 mm was obtained was determined as A, and obtained. The case where there was none was determined as B.

<Thermal conductivity>
For each of Examples 2-1 to 2-7 and Comparative examples 2-1 to 2-2, the thermal conductivity was measured by a one-way steady-state heat flow comparison method (SCHF) at a measurement temperature of 33 ° C. in accordance with JIS H7903: 2008. It was measured.

<Softness>
For each of Examples 2-1 to 2-7 and Comparative examples 2-1 to 2-2, the penetration amount was measured as an index of softness at a measurement temperature of 23 ± 3 ° C. in accordance with JIS A5752: 1994.

(Test results)
The test results are shown in Table 2-2. According to Table 2-2, in Examples 2-1 to 2-7, a heat conductive sheet having a thickness of 3 mm was obtained, and both the heat conductivity and the softness were high. On the other hand, in Comparative Example 2-1, a heat conductive sheet having a thickness of 3 mm was not obtained, and neither the heat conductivity nor the softness could be measured. In Comparative Example 2-2, a heat conductive sheet having a thickness of 3 mm was obtained, and although having sufficient softness, it was found that the level of heat conductivity was low.

(Embodiment 3)
FIG. 3 shows a heat conductive laminated structure 30 according to the third embodiment.

The heat conductive laminated structure 30 according to the third embodiment includes an insulating layer 31, a sheet-like heat conductive polymer composition 32 laminated on the insulating layer 31, and a laminate on the heat conductive polymer composition 32. Metal layer 33 provided. And the heat conductive polymer composition 32 contains a base polymer and a heat conductive filler. In addition, the surface of the insulating layer 31 that is in contact with the heat conductive polymer composition 32 is subjected to a surface treatment that enhances adhesion to the heat conductive polymer composition 32.

By the way, when the heat conductive sheet is provided on the electronic device via the insulating layer, there is a problem that heat dissipation is inferior to the case where the heat conductive sheet is provided so as to directly contact the electronic device. . However, according to the heat conductive laminated structure 30 according to the third embodiment, the heat conductive polymer composition 32 contains the base polymer and the heat conductive filler, and the heat conductive polymer composition of the insulating layer 31. Since a surface treatment for enhancing the adhesion to the thermally conductive polymer composition 32 is applied to the contact surface with the thermally conductive polymer composition 32, the interfacial thermal resistance between the insulating layer and the thermally conductive polymer composition is reduced. Therefore, even if the insulating layer 31 is provided between the heat generating article and the thermally conductive polymer composition 32, excellent heat dissipation can be obtained. This is presumed to be due to the suppression of the formation of nanoscale pores at the interface between the insulating layer 31 and the thermally conductive polymer composition 32, which increases the interfacial thermal resistance and lowers the thermal conductivity. In addition, in the heat conductive laminated structure 30 according to the third embodiment, high adhesion of the heat conductive polymer composition 32 to the insulating layer 31 can be obtained.

Examples of the insulating layer 31 include a resin sheet of a thermoplastic resin or a thermosetting resin; a rubber sheet. The insulating layer 31 is preferably a resin sheet of a thermoplastic resin from the viewpoint of increasing the adhesion to the heat conductive polymer composition 32 and obtaining excellent heat dissipation. Examples of the thermoplastic resin include polyethylene (PE), polypropylene (PP), polycarbonate (PC), polytetrafluoroethylene (PTFE), acrylonitrile butadiene styrene copolymer (ABS), polyamide (PA), and polyimide (PI). ), Polyamide imide (PAI), polyethylene terephthalate (PET), polybutylene terephthalate (PBT) and the like. The thickness of the insulating layer 31 is, for example, 0.1 mm or more and 1.0 mm or less.

The surface treatment applied to the insulating layer 31 is intended to improve the adhesiveness to the heat conductive polymer composition 32 and to obtain excellent heat dissipation, so that the contact surface of the insulating layer 31 with the heat conductive polymer composition 32 is improved. Preferably, the treatment is a modification with a functional group. Examples of such a functional group include a hydroxy group, a carboxyl group, a carbonyl group, an amino group, an epoxy group, a cation-containing group, and an anion-containing group. The functional group preferably contains one or more of these. The functional group on the surface of the insulating layer 31 preferably includes a suitable one corresponding to the base polymer of the thermally conductive polymer composition 32. For example, when the base polymer of the thermally conductive polymer composition 32 includes a polymer having a hydroxy group, the functional group on the surface of the insulating layer 31 preferably includes a hydroxy group and / or an amino group. When the base polymer of the thermally conductive polymer composition 32 contains silicone, the functional group on the surface of the insulating layer 31 preferably contains a vinyl group and / or an allyl group. The structure modified with a carbonyl group includes acid anhydride modification such as maleic anhydride modification. Configurations modified with a cation-containing or anion-containing group include ionomers.

Examples of the surface treatment include a plasma treatment, a flame treatment, a corona discharge treatment, an ozone spraying treatment, an ultraviolet irradiation treatment, a coating treatment, and a silane coupling agent treatment. The surface treatment preferably includes one or more of these, and from the viewpoint of enhancing the adhesion of the insulating layer 31 to the thermally conductive polymer composition 32 and obtaining excellent heat dissipation, plasma treatment and More preferably, it includes a flame treatment. In addition, the same surface treatment may be performed on the contact surface of the insulating layer 31 with the heat-generating article.

(4) The thermally conductive polymer composition 32 contains a base polymer and a thermally conductive filler dispersed in the base polymer. The heat conductive polymer composition 32 is preferably a heat conductive putty composition. The heat conductive polymer composition 32 may further contain a viscosity modifier such as organic bentonite. The thickness of the thermally conductive polymer composition 32 is, for example, 0.1 mm or more and 20 mm or less.

The base polymer preferably contains a liquid polymer. The content of the liquid polymer in the base polymer is preferably 50% by mass or more, more preferably 80% by mass or more, further preferably 90% by mass or more, and most preferably 100% by mass. That is, the base polymer preferably contains a liquid polymer as a main component.

The viscosity of the liquid polymer at 30 ° C. is preferably 0.5 Pa · s or more and 100 Pa · s or less, from the viewpoint of increasing the adhesion between the heat conductive polymer composition 32 and the insulating layer 31 and obtaining excellent heat dissipation. More preferably, it is 1.0 Pa · s or more and 90 Pa · s or less. The viscosity of the liquid polymer is measured according to JIS K2283: 2000.

The number average molecular weight of the liquid polymer is preferably 800 or more and 4000 or less, more preferably 1000 or more and 3500 or less, from the viewpoint of enhancing the adhesion of the thermally conductive polymer composition 32 to the insulating layer 31 and obtaining excellent heat dissipation. is there. The number average molecular weight of the liquid polymer is measured according to ASTM D2503.

(4) The liquid polymer preferably contains a liquid polymer A having a hydroxy group from the viewpoint of increasing the adhesion of the thermally conductive polymer composition 32 to the insulating layer 31 and obtaining excellent heat dissipation. From the same viewpoint, the liquid polymer A is preferably one in which the basic skeleton of the hydrocarbon is modified with a hydroxy group. The basic skeleton of the hydrocarbon is not particularly limited, and examples thereof include a saturated hydrocarbon, an unsaturated hydrocarbon, an alicyclic hydrocarbon, and an aromatic hydrocarbon. Specifically, examples of the basic skeleton of the hydrocarbon include, for example, polybutadiene; polyisoprene; and polyolefins such as polyethylene, polypropylene, and ethylene-propylene copolymer. The basic skeleton of the hydrocarbon preferably contains one or more of these.

The content of the hydroxy group in the liquid polymer A is preferably from 0.3 mol / kg to 3 mol / kg, and more preferably from the viewpoint of enhancing the adhesiveness of the thermally conductive polymer composition 32 to the insulating layer 31 and obtaining excellent heat dissipation. Preferably it is 0.5 mol / kg or more and 2 mol / kg or less. The hydroxy group content in the liquid polymer A is calculated from the following formula (1) based on the hydroxyl valency measured according to JIS K1557-1: 2007.
Hydroxy group content (mol / kg) = hydroxyl valence (mgKOH / g) / A ... (1)
(A: molecular weight of KOH)

The hydroxy group may modify the terminal of the hydrocarbon basic skeleton, may modify the middle part of the hydrocarbon basic skeleton, and may modify both the terminal and the intermediate part of the hydrocarbon basic skeleton. May be. The hydroxy group preferably modifies at least the terminal of the basic skeleton of the hydrocarbon from the viewpoint of enhancing the adhesion of the heat conductive polymer composition 32 to the insulating layer 31 and obtaining excellent heat dissipation. It is more preferable that both the terminal and the intermediate part of the basic skeleton are modified.

市 販 Examples of commercially available liquid polymer A in which the terminal of the basic skeleton of the hydrocarbon is modified with a hydroxy group include G series and GI series of NISSO-PB manufactured by Nippon Soda Co., Ltd., and polytail manufactured by Mitsubishi Chemical Corporation. Examples of the commercially available liquid polymer A in which both the terminal and the intermediate part of the basic skeleton of the hydrocarbon are modified with hydroxy groups include, for example, Poly 出 bd, Poly 、 ip, EPOL and the like manufactured by Idemitsu Kosan Co., Ltd.

The base polymer may include a liquid polymer B having no hydroxy group other than the liquid polymer A. As the liquid polymer B, a polymer having a basic skeleton of a hydrocarbon is preferable, and examples thereof include a naphthene-based polymer, a paraffin-based polymer, and an aromatic polymer. The liquid polymer B preferably contains one or more of these, and from the viewpoint of obtaining excellent shape following properties and high thermal conductivity of the thermally conductive polymer composition 32, a paraffin-based polymer and / or More preferably, it contains an aromatic polymer.

Examples of commercially available naphthenic polymers include SNH series manufactured by Sankyo Yuka Kogyo Co., Ltd., and SUNTHENE series manufactured by Nippon Sun Oil Co., Ltd. Examples of commercially available paraffin-based polymers include, for example, NA Solvent manufactured by NOF Corporation, PW series manufactured by Idemitsu Kosan, SUNPAR series manufactured by Nippon Sun Oil Co., Ltd., B series and BI series of NISSO-PB manufactured by Nippon Soda, and NOF Corporation Nippon Oil Polybutene Series, JXTG Energy Corporation Nisseki Polybutene Series, and the like. Commercially available aromatic polymers include, for example, JSO AROMA 790.

The content of the liquid polymer B in the base polymer is preferably 50% by mass or less, more preferably 20% by mass or less, and further preferably 10% by mass or less. That is, when the base polymer includes the liquid polymer B, it is preferable to include the liquid polymer B as an auxiliary component. The base polymer may include a polymer other than the liquid polymer, such as a cured product obtained by curing a liquid material by crosslinking or the like.

Examples of the heat conductive filler include metal oxides such as aluminum oxide, magnesium oxide, beryllium oxide, zinc oxide, silicon oxide, and titanium oxide; metal hydroxides such as aluminum hydroxide, aluminum nitride, boron nitride, and silicon nitride. Metal such as gold, silver, copper, aluminum, tungsten, titanium, nickel, iron and alloys of two or more thereof; carbon compounds such as graphite (graphite), carbon fiber, fullerene, graphene and carbon nanotube And the like. The heat conductive filler preferably contains one or more of these, and more preferably contains one or more of metal oxides, metal hydroxides, and metal nitrides, More preferably, it contains aluminum oxide. The shape of the heat conductive filler is preferably spherical or disc-shaped from the viewpoint of enhancing the adhesion of the heat conductive polymer composition 32 to the insulating layer 31 and obtaining excellent heat dissipation. The heat conductive filler may have an organic functional group such as a vinyl group, an epoxy group, an amino group, a methacryl group, an isocyanate group, and a mercapto group on the surface by a surface treatment with a silane coupling agent or the like. This organic functional group preferably contains one or more of these, and more preferably contains one or more of a vinyl group, an amino group, and a methacryl group.

The average particle diameter (d ₅₀ ) of the heat conductive filler is preferably 0.5 μm or more and 100 μm or less, from the viewpoint of increasing the adhesion of the heat conductive polymer composition 32 to the insulating layer 31 and obtaining excellent heat dissipation. Preferably it is 3 μm or more and 80 μm or less. This average particle diameter (d ₅₀ ) is measured by the Coulter counter method. From the same viewpoint, the particle size distribution of the heat conductive filler preferably has a plurality of peaks. Therefore, it is preferable that the heat conductive filler include a plurality of types having different average particle diameters (d ₅₀ ). When the heat conductive filler contains two kinds having different average particle diameters (d ₅₀ ), for example, the peak on the small diameter side is in the range of 0.3 μm or more and 10 μm or less, and the peak on the large diameter side is 20 μm or more and 100 μm or less. Is preferred. When the heat conductive filler contains three kinds having different average particle diameters (d ₅₀ ), the peak on the small diameter side is in the range of 0.1 μm or more and 1 μm or less, the peak of the intermediate diameter is in the range of 1 μm or more and 60 μm or less, it is preferred that the peak of the large diameter side is in 10μm or 100μm or less (larger diameter _{d 50> d} 50 of intermediate diameter).

The content of the heat conductive filler in the heat conductive polymer composition 32 is preferably 500 parts by mass or more and 3000 parts by mass or less, more preferably 1000 parts by mass or more and 2600 parts by mass or less, based on 100 parts by mass of the base polymer. Is from 1200 parts by mass to 2400 parts by mass.

According to JIS H7903: 2008, the thermal conductivity of the thermally conductive polymer composition 32 measured at a measurement temperature of 33 ° C. (one-way steady-state heat flow comparison method (SCHF)) is preferably 2 W / m · K or more. It is preferably at least 50 W / m · K.

The heat conductive polymer composition 32 may be the heat conductive putty composition of the first or second embodiment.

As the metal layer 33, for example, a metal sheet of an alloy such as aluminum, iron, gold, silver, copper, and stainless steel may be used. The thickness of the metal layer 33 is, for example, 0.5 mm or more and 5 mm or less.

The adhesion between the insulating layer 31 and the thermally conductive polymer composition 32 in the thermally conductive laminated structure 30 according to the third embodiment is obtained by removing the thermally conductive polymer composition 32 from the insulating layer 31 of the thermally conductive laminated structure 30 at room temperature. The residual amount of the thermally conductive polymer composition 32 on the surface of the insulating layer 31 when peeled off at a rate of 1 mm / min in the direction perpendicular to the bonding surface is shown in Table 1 of JIS @ K5600-5-6: 1999. It is evaluated by classification. The classification of the adhesion is preferably 0, 1, 2, or 3, and more preferably 0, 1, or 2. In addition, the white portion in the diagram of Table 1 in JIS K5600-5-6: 1999 corresponds to the residual heat conductive polymer composition 32.

The heat conductive laminated structure 30 according to the third embodiment is obtained by laminating the insulating layer 31, the sheet-shaped heat conductive polymer composition 32, and the metal layer 33, and heating and compressing them to perform lamination. Can be. The sheet-like thermally conductive polymer composition 32 is prepared by mixing a thermally conductive filler with a base polymer containing a liquid polymer and kneading the mixture with a kneading machine such as a kneader. Can be prepared by molding into a sheet by a known molding method such as press molding.

FIG. 4 shows a heat dissipation structure 40 using the heat conductive laminated structure 30 according to the third embodiment.

In the heat dissipating structure 40, in the heat conductive laminated structure 30 according to the third embodiment, the surface of the insulating layer 31 on the side opposite to the heat conductive polymer composition 32 side is in surface contact with the heat generating article 41, and the heat conduction is performed. The conductive polymer composition 32 is provided on the surface of the heating article 41 via the insulating layer 31. Then, in the heat dissipation structure 40, heat from the heat generating article 41 is conducted to the heat conductive polymer composition 32 via the insulating layer 31 and then radiated to the outside via the metal layer 33. At this time, the surface of the insulating layer 31 of the heat conductive laminated structure 30 according to the third embodiment which is in contact with the heat conductive polymer composition 32 is subjected to a surface treatment for increasing the adhesion to the heat conductive polymer composition 32. As a result, the interfacial thermal resistance between them is reduced, so that excellent heat dissipation can be obtained. Here, as a specific heat dissipation structure 40, for example, a lithium ion secondary battery module in which a module main body having a plurality of lithium ion secondary batteries is used as a heat generating article 41 is exemplified.

In the third embodiment, the following invention is disclosed.

<1> A heat conductive laminated structure including an insulating layer and a heat conductive polymer composition laminated on the insulating layer, wherein the heat conductive polymer composition includes a base polymer and a heat conductive polymer composition. A heat conductive laminated structure comprising a filler, and a surface treatment for improving the adhesion to the heat conductive polymer composition on a surface of the insulating layer in contact with the heat conductive polymer composition.

<2> In the thermally conductive laminated structure according to <1>, the surface treatment is a treatment for modifying a surface of the insulating layer in contact with the thermally conductive polymer composition with a functional group. Laminated structure.

<3> In the heat conductive laminated structure according to <2>, the functional group is one of a hydroxy group, a carboxyl group, a carbonyl group, an amino group, an epoxy group, a cation-containing group, and an anion-containing group. A thermally conductive layered structure comprising one or more species.

<4> The thermally conductive laminated structure according to any one of <1> to <3>, wherein the surface treatment includes a plasma treatment and / or a flame treatment.

<5> The thermally conductive laminated structure according to any one of <1> to <4>, wherein the base polymer includes a liquid polymer.

<6> The thermally conductive laminated structure according to <5>, wherein the liquid polymer has a hydroxy group.

<7> In the heat conductive laminated structure according to <5> or <6>, the heat conduction is such that the basic skeleton of the liquid polymer contains one or more of polybutadiene, polyisoprene, and polyolefin. Laminated structure.

<8> In the heat conductive laminated structure according to any one of <1> to <7>, the heat conductive filler is one or more of a metal oxide, a metal hydroxide, and a metal nitride. A thermally conductive laminated structure including two or more types.

<9> The thermally conductive laminated structure according to <8>, wherein the thermally conductive filler includes aluminum oxide.

<10> The heat conductive laminated structure according to any one of <1> to <9>, wherein the heat conductive polymer composition is provided on a surface of a heat generating article via the insulating layer. Heat dissipation structure.

<11> The heat dissipation structure according to <10>, wherein the heat dissipation structure is a lithium ion secondary battery module.

[Example 3]
(Thermally conductive laminate)
Thermally conductive laminates of the following Examples 3-1 to 3-4 and Comparative examples 3-1 to 3-4 were produced.

<Example 3-1>
Liquid polymer 1 (Poly bd R-45HT, manufactured by Idemitsu Kosan Co., Ltd., hydroxy group content: 0.83 mol / kg, viscosity (30 ° C.): 5 Pa · s, number average molecular weight) : 2800) as a base polymer and 100 parts by mass of the base polymer, as a heat conductive filler, spherical aluminum oxide (spherical alumina: Alnabeads CB-A70 manufactured by Showa Denko KK, average particle diameter (d ₅₀ ): 71 μm, Number of particle size distribution peaks: 1) 1540 parts by mass, spherical aluminum oxide (spherical alumina: alumina beads CB-P40 manufactured by Showa Denko KK) average particle size (d ₅₀ ): 40 μm, Number of particle size distribution peaks: 1) 330 parts by mass And spherical aluminum oxide (polyhedral spherical advanced alumina AA-04 manufactured by Sumitomo Chemical Co., Ltd., average Child diameter _(d 50): 0.5 [mu] m, the particle size distribution peak: 1) 330 parts by weight blended with thermally conductive polymer composition was prepared by kneading in a kneader, a thickness of 2.0mm it Into a sheet.

プ ラ ズ マ Plasma treatment was performed on the surface of one side of the insulating layer of the polyethylene resin sheet having a thickness of 0.5 mm to modify the surface with a hydroxy group. The plasma treatment was performed using a vacuum plasma apparatus (RIE-S-200A) manufactured by Kaki Semiconductor Co., Ltd., after irradiating with argon gas, introducing water-bubbled argon gas, with a plasma output of 200 W and an irradiation time of 5 minutes. It was confirmed that the contact angle of the polyethylene resin sheet with water before and after the plasma treatment was changed from 101 ° to 28 °. In addition, when the surface of the polyethylene resin sheet after the plasma treatment was analyzed by X-ray photoelectron spectroscopy (ESCA), it was confirmed that CO bonding had occurred.

Immediately after the plasma treatment was applied to the polyethylene resin sheet of the insulating layer, the sheet-like heat conductive polymer composition was laminated and laminated so as to be in contact with the surface on the side subjected to the plasma treatment. The heat conductive laminate was referred to as Example 3-1.

<Example 3-2>
As a base polymer, a liquid polymer 2 in which the terminal and intermediate portions of polybutadiene are modified with hydroxy groups (Poly bd R-15HT, manufactured by Idemitsu Kosan Co., Ltd., hydroxy group content: 1.83 mol / kg, viscosity (30 ° C.): 1.5 Pa) S, number average molecular weight: 1200), and a heat conductive laminate produced in the same manner as in Example 3-1 except for using Example 3-2 was used as Example 3-2.

<Example 3-3>
As a base polymer, a liquid polymer 3 (Polyip Idemitsu Kosan Co., Ltd., hydroxy group content: 0.83 mol / kg, viscosity (30 ° C.): 7.5 Pa · s) A thermally conductive laminate manufactured in the same manner as in Example 3-1 except that (number average molecular weight: 2500) was used was referred to as Example 3-3.

<Example 3-4>
As a base polymer, liquid polymer 4 in which the terminal and intermediate portions of polybutadiene were modified with hydroxy groups (EPOL, manufactured by Idemitsu Kosan Co., Ltd., hydroxy group content 0.9 mol / kg, viscosity (30 ° C.): 75 Pa · s, number average molecular weight: Example 3-4 was used as a thermally conductive laminate manufactured in the same manner as in Example 3-1 except for using Example 2500.

<Comparative Examples 3-1 to 3-4>
The thermally conductive laminates produced in the same manner as in Examples 3-1 to 3-4 except that the plasma treatment was not performed on the polyethylene resin sheet of the insulating layer were Comparative Examples 3-1 to 3-4, respectively.

(Test method)
<Thermal conductivity>
The thermal conductivity of each of Examples 3-1 to 3-4 and Comparative examples 3-1 to 3-4 was measured by a one-way steady state heat flow comparison method (SCHF) at a measurement temperature of 33 ° C. in accordance with JIS H7903: 2008. It was measured.

<Adhesion>
For each of Examples 3-1 to 3-4 and Comparative examples 3-1 to 3-4, the thermally conductive polymer composition was applied at room temperature from the polyethylene resin sheet of the insulating layer at a rate of 1 mm / min in the direction perpendicular to the bonding surface. The residual amount of the thermally conductive polymer composition on the surface of the insulating layer when peeled at a speed of 0 is classified into 0, 1, 2, 3, 4, or 5 according to Table 1 of JIS K5600-5-6: 1999. did. In addition, the white part of the figure of Table 1 of JISK5600-5-6: 1999 corresponds to the residual heat conductive polymer composition.

(Test results)
Table 3 shows the test results. According to Table 3, Examples 3-1 to 3-4 in which the plasma treatment was performed on the polyethylene resin sheet of the insulating layer were compared with Comparative Examples 3-1 to 3-4 in which the plasma treatment was not performed on the insulating layer. It can be seen that the thermal conductivity is high despite using the same thermally conductive polymer composition. This indicates that Examples 3-1 to 3-4 have lower interfacial thermal resistance between the insulating layer and the thermally conductive polymer composition than Comparative Examples 3-1 to 3-4. In addition, from the adhesion test, Examples 3-1 to 3-4 show that the insulating layer and the comparative examples 3-1 to 3-4 have the same heat conductive polymer composition as the comparative examples 3-1 to 3-4. It can be seen that the adhesiveness with the thermally conductive polymer composition is high.

The present invention is useful in the technical field of a heat conductive putty composition, and a heat conductive sheet and a heat dissipation structure using the same.

10 (lithium ion) secondary battery module (heat dissipation structure)
11 Module body (heating product)
111 (lithium ion) secondary battery 112 Battery holder 112a Battery holder 112b Round hole 12 Thermal conductive sheet 30 Thermal conductive laminated structure 31 Insulating layer 32 Thermal conductive polymer composition 33 Metal layer 40 Heat dissipation structure 41 Heat generating article

Claims (13)

1. A heat conductive putty composition containing a base polymer containing a liquid polymer having a hydroxy group as a main component and a heat conductive filler,
   A thermally conductive putty composition wherein the content of the thermally conductive filler is 500 parts by mass or more and 3000 parts by mass or less with respect to 100 parts by mass of the base polymer.
2. The thermally conductive putty composition according to claim 1,
   A thermally conductive putty composition, wherein the basic skeleton of the liquid polymer having a hydroxy group contains one or more of polybutadiene, polyisoprene, and polyolefin.
3. The thermally conductive putty composition according to claim 2,
   A thermally conductive putty composition wherein the hydroxy group modifies at least the terminal of the basic skeleton of the hydrocarbon.
4. The thermally conductive putty composition according to any one of claims 1 to 3,
   A thermally conductive putty composition wherein the hydroxy group content in the liquid polymer having a hydroxy group is from 0.3 mol / kg to 3 mol / kg.
5. The thermally conductive putty composition according to any one of claims 1 to 4,
   A thermally conductive putty composition, wherein the base polymer contains a liquid polymer having no hydroxy group as an auxiliary component.
6. The thermally conductive putty composition according to claim 5,
   A thermally conductive putty composition, wherein the liquid polymer having no hydroxy group contains one or more of a naphthene-based polymer, a paraffin-based polymer, and an aromatic-based polymer.
7. The thermally conductive putty composition according to any one of claims 1 to 6,
   A thermally conductive putty composition, wherein the thermally conductive filler contains one or more of a metal oxide, a metal hydroxide, and a metal nitride.
8. The thermally conductive putty composition according to claim 7,
   A thermally conductive putty composition wherein the thermally conductive filler contains aluminum oxide.
9. The thermally conductive putty composition according to any one of claims 1 to 8,
   A thermally conductive putty composition, wherein the shape of the thermally conductive filler is spherical or discoid.
10. The thermally conductive putty composition according to any one of claims 1 to 9,
    A thermally conductive putty composition having a plurality of peaks in the particle size distribution of the thermally conductive filler.
11. A heat conductive sheet obtained by molding the heat conductive putty composition according to any one of claims 1 to 10 into a sheet.
12. A heat dissipating structure in which the heat conductive sheet according to claim 11 is attached to a surface of a heat generating article.
13. The heat dissipation structure according to claim 12,
    A heat dissipation structure, wherein the heat dissipation structure is a lithium ion secondary battery module.

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