阅读说明：本技术 二液固化型组合物的组合、热传导性固化物及电子仪器 (Two-component curable composition combination, thermally conductive cured product, and electronic device ) 是由 加藤真洋 于 2019-10-10 设计创作，主要内容包括：二液固化型组合物的组合,其具备第一剂和第二剂,所述第一剂包含具有支链状结构且至少在末端或侧链具有乙烯基的有机聚硅氧烷、热传导性填料、二氧化硅粉末和铂催化剂,在25℃、剪切速度10s～(－1)下的粘度为20～150Pa·s,所述第二剂包含具有支链状结构且至少在末端或侧链具有乙烯基的有机聚硅氧烷、至少在末端或侧链具有氢甲硅烷基的聚二甲基硅氧烷、热传导性填料和二氧化硅粉末,在25℃、剪切速度10s～(－1)下的粘度为20～150Pa·s。(A two-component curable composition comprising a first component comprising an organopolysiloxane having a branched structure and having a vinyl group at least at the terminal or in the side chain, a thermally conductive filler, a silica powder, and a platinum catalyst, and having a shear rate of 10s at 25 ℃, and a second component －1 The viscosity of the composition is 20 to 150 pas, the second agent contains organopolysiloxane having a branched structure and having a vinyl group at least at a terminal or a side chain, polydimethylsiloxane having a hydrosilyl group at least at a terminal or a side chain, thermally conductive filler and silica powder, and the shear rate is 10s at 25 DEG C －1 The viscosity at room temperature is 20 to 150 pas.)

1. A two-component curable composition comprising a first component and a second component,

the first agent comprises an organopolysiloxane having a branched structure and a vinyl group at least at a terminal or a side chain, a thermally conductive filler, a silica powder, and a platinum catalyst, and has a shear rate of 10s at 25 DEG C^－1The viscosity of the resulting mixture is 20 to 150 pas,

the second agent comprises an organopolysiloxane having a branched structure and a vinyl group at least at a terminal or a side chain, a polydimethylsiloxane having a hydrosilyl group at least at a terminal or a side chain, a thermally conductive filler and a silica powder, and has a shear rate of 10s at 25 DEG C^－1The viscosity at room temperature is 20 to 150 pas.

2. The two-pack curable composition according to claim 1, wherein the thermally conductive filler is contained in the first formulation in an amount of 400 to 1000 parts by mass based on 100 parts by mass of the organopolysiloxane contained in the first formulation,

the content of the silica powder in the first agent is 0.2 to 2.0 parts by mass relative to 100 parts by mass of the content of the organopolysiloxane in the first agent.

3. The two-pack curable composition combination according to claim 1 or 2, wherein the content of the thermally conductive filler in the second agent is 400 to 1000 parts by mass based on 100 parts by mass of the total content of the organopolysiloxane and the polydimethylsiloxane in the second agent,

the content of the silica powder in the second agent is 0.2-2.0 parts by mass relative to 100 parts by mass of the total content of the organopolysiloxane and the polydimethylsiloxane in the second agent.

4. A thermally conductive cured product obtained from a mixture of the first agent and the second agent in the combination of the two-component curable composition according to any one of claims 1 to 3, having a thermal conductivity of 1.0 to 3.0W/mK.

5. An electronic device comprising an electronic component, the thermally conductive cured product according to claim 4, and a case for housing the electronic component and the thermally conductive cured product,

the electronic component and the case are in contact with each other through the thermally conductive cured material.

Technical Field

The present invention relates to a combination of two-component curable compositions, thermally conductive cured products, and electronic devices.

Background

As heat-generating electronic components such as CPUs (central processing units) of computers are reduced in size and increased in power, the amount of heat generated by these electronic components per unit area is becoming extremely large. This amount of heat is even up to about 20 times the amount of heat of the iron. In order to prevent such heat-generating electronic components from malfunctioning for a long period of time, it is necessary to cool the heat-generating electronic components. When a heat sink (heat sink) or a case made of metal is used for cooling, if a heat-generating electronic component is brought into direct contact with the heat sink or the like, microscopically, air is present at the interface thereof, which may cause heat conduction failure. Therefore, the heat is efficiently conducted by interposing the heat conductive material between the heat-generating electronic component and the heat sink or the like.

As the thermally conductive material, particularly, grease (grease) having fluidity, in which thermally conductive powder is filled in liquid silicone, is preferably used from the viewpoint of easy heat conduction. As the grease, a grease obtained by adding a thermally conductive powder to a low-viscosity silicone such as a low-molecular-weight silicone is known as a base oil of a liquid silicone such as a silicone oil (for example, patent documents 1 to 4).

Documents of the prior art

Patent document

Patent document 1: japanese laid-open patent publication No. 2009-286855

Patent document 2: japanese patent laid-open publication No. 2015-140395

Patent document 3: japanese patent laid-open publication No. 2014-105283

Patent document 4: japanese laid-open patent application No. 2010-150399

Disclosure of Invention

Problems to be solved by the invention

In the case of using a grease having a low viscosity, the grease may drip when used in a vertical manner, and as a result, sufficient heat dissipation may not be possible. Further, when mounted on an electronic component, a gap is generated due to the fact that vibration or the like cannot follow the warpage generated between the heat generating component and the cooling case, and there is a problem that reliability as a heat conductive material is lowered.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a combination of two-component curable compositions which can suppress dripping even in use in a vertical manner and can suppress a decrease in reliability against vibration or the like when mounted on an electronic component, a thermally conductive cured product obtained from the combination of two-component curable compositions, and an electronic device including the thermally conductive cured product.

Means for solving the problems

The present invention provides a combination of a two-component curable composition having a first component and a second component. The first agent comprises an organopolysiloxane having a branched structure and a vinyl group at least at the terminal or side chain, a thermally conductive filler, a silica powder, and a platinum catalyst, and has a shear rate of 10s at 25 DEG C^－1The viscosity at room temperature is 20 to 150 pas. The second agent comprises an organopolysiloxane having a branched structure and a vinyl group at least at the terminal or side chain, a polydimethylsiloxane having a hydrosilyl group at least at the terminal or side chain, a thermally conductive filler and a silica powder, and has a shear rate of 10s at 25 DEG C^－1The viscosity at room temperature is 20 to 150 pas.

The content of the thermally conductive filler in the first agent may be 400 to 1000 parts by mass with respect to 100 parts by mass of the content of the organopolysiloxane in the first agent, and the content of the silica powder in the first agent may be 0.2 to 2.0 parts by mass with respect to 100 parts by mass of the content of the organopolysiloxane in the first agent.

The content of the thermally conductive filler in the second agent may be 400 to 1000 parts by mass with respect to 100 parts by mass of the total content of the organopolysiloxane and the polydimethylsiloxane in the second agent, and the content of the silica powder in the second agent may be 0.2 to 2.0 parts by mass with respect to 100 parts by mass of the total content of the organopolysiloxane and the polydimethylsiloxane in the second agent.

The present invention also provides a thermally conductive cured product having a thermal conductivity of 1.0 to 3.0W/mK, which is obtained from a mixture of the first agent and the second agent in the combination of the two-component curable composition of the present invention.

The present invention also provides an electronic device comprising an electronic component, the thermally conductive cured product of the present invention, and a case for housing the electronic component and the thermally conductive cured product, wherein the electronic component and the case are in contact with each other through the thermally conductive cured product.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present invention, it is possible to provide a combination of two-component curable compositions which can suppress dripping even in use in a vertical orientation and can suppress a decrease in reliability against vibration or the like when mounted on an electronic component, a thermally conductive cured product obtained from the combination of two-component curable compositions, and an electronic device including the thermally conductive cured product.

Drawings

FIG. 1 is a schematic cross-sectional view showing an embodiment of an electronic apparatus.

FIG. 2 is a schematic view for explaining a test method of dripping property in examples.

FIG. 3 is a schematic view for explaining a test method of dripping property in examples.

Detailed Description

Hereinafter, embodiments of the present invention will be described in detail. However, the present invention is not limited to the following embodiments.

[ combination of two-part curable compositions ]

The combination of the two-component curable composition of the present embodiment includes a first component and a second component. Hereinafter, each component contained in the first dose and the second dose will be described.

< first dose >

The first agent contains a specific organopolysiloxane (component a 1), a thermally conductive filler (component a 2), a silica powder (component A3), and a platinum catalyst (component a 4).

(A1 component: organopolysiloxane)

The organopolysiloxane of the present embodiment has a vinyl group at a terminal or a side chain. Generally, the organopolysiloxane having vinyl groups is an organopolysiloxane in which at least a part of R of the Si-R moiety (wherein R is a substituted or unsubstituted 1-valent hydrocarbon group) in the organopolysiloxane molecule is vinyl groups. Such an organopolysiloxane may have a structural unit represented by the following general formula (a 1-1) or a terminal structure represented by the general formula (a 1-2). The organopolysiloxane may have, for example, a structural unit represented by the general formula (a 1-1) and a structural unit represented by the general formula (a 1-3), or may have a terminal structure represented by the general formula (a 1-2) and a structural unit represented by the general formula (a 1-3). However, the organopolysiloxane of the present embodiment is not limited to the organopolysiloxane having these structural units or terminal structures, and may have 2 or more vinyl groups at the terminal or side chain, for example.

[ chemical formula 1]

The content of the vinyl group in the organopolysiloxane is preferably 0.01 to 15 mol%, more preferably 0.01 to 5 mol%. The "vinyl group content" in the present invention means the mol% of the vinyl group-containing siloxane structural unit based on 100 mol% of the total structural units constituting the organopolysiloxane. Wherein the content of the vinyl group is a value assuming that the vinyl group is 1 with respect to 1 vinyl group-containing siloxane structural unit.

The vinyl content was measured by the following method.

The vinyl content was determined by NMR. Specifically, for example, measurement was performed by dissolving an organopolysiloxane having a vinyl group in deuterated chloroform as a deuterated solvent by ECP-300 NMR manufactured by JEOL. The proportion of vinyl groups based on 100 mol% (vinyl group + hydrosilyl group + Si-methyl group) was defined as the vinyl group content mol%.

Examples of the substituted or unsubstituted 1-valent hydrocarbon group other than the vinyl group include alkyl groups such as a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, an octyl group, a nonyl group, a decyl group, and a dodecyl group; cycloalkyl groups such as cyclopentyl and cyclohexyl; aryl groups such as phenyl, tolyl, xylyl, and naphthyl; aralkyl groups such as benzyl, 2-phenylethyl, and 2-phenylpropyl; and halogenated alkyl groups such as chloromethyl, 3,3, 3-trifluoropropyl, and 3-chloropropyl. From the viewpoint of synthesis and economy, 90% or more of the above groups are preferably methyl groups, and the organopolysiloxane of the present embodiment is more preferably polydimethylsiloxane having a vinyl group.

The organopolysiloxane of the present embodiment has a branched structure. By having a branched structure, the viscosity before curing is low, the viscosity is not excessively high even if the thermally conductive filler is filled, the coatability is excellent, and high shear displacement and elongation at break can be achieved after curing.

Whether or not the organopolysiloxane has a branched structure can be determined as follows: by using a nuclear magnetic resonance apparatus AVANCEIII-500 (trade name) manufactured by BRUKER²⁹Si-NMR measurement was performed to examine the presence or absence of peaks of-55 to-66 ppm or-100 to-110 ppm as chemical shifts derived from a branched structure.

The viscosity of the organopolysiloxane of the present embodiment is preferably 100 to 1000 mPas at 25 ℃. When the viscosity of the organopolysiloxane at 25 ℃ is 100 mPas or more, the shear displacement and elongation at break of the cured product described below can be sufficiently ensured, and a decrease in reliability against vibration or the like can be suppressed when the organopolysiloxane is mounted on an electronic component. Further, if the viscosity of the organopolysiloxane at 25 ℃ is 1000mPa · s or less, the viscosity will not become too high when the thermally conductive filler is filled, and the coatability and adhesion to the heat generating component can be satisfactorily ensured. From such a viewpoint, the viscosity of the organopolysiloxane at 25 ℃ is preferably 200 to 800 mPas, more preferably 300 to 700 mPas.

The viscosity of the organopolysiloxane at 25 ℃ can be measured using a digital viscometer "DV-1" manufactured by BROOKFIELD. Using a rotor No.1 with the RV spindle set (spindle set), the rotor was immersed in the organopolysiloxane using a vessel equipped with the rotor and capable of holding the organopolysiloxane up to the base line, and the viscosity was measured at 25 ℃ at a rotation number of 10 rpm.

(A2 component: thermally conductive filler)

The thermally conductive filler has a thermal conductivity of, for example, 10W/mK or more. Examples of the thermally conductive filler include aluminum oxide (hereinafter also referred to as "aluminum oxide"), aluminum nitride, boron nitride, silicon nitride, zinc oxide, aluminum hydroxide, metallic aluminum, magnesium oxide, copper, and silver. These may be used alone or in combination of two or more. Alumina is preferred from the viewpoint of filling properties and thermal conductivity. In the present specification, the term "thermally conductive filler" does not include the thermally conductive filler of the following silica powder.

The thermally conductive filler preferably has an average particle diameter of 1 to 50 μm, and more preferably a thermally conductive filler (A2-1) having an average particle diameter of 40 to 50 μm and a thermally conductive filler (A2-2) having an average particle diameter of 1 to 10 μm are used in combination. In this case, the blending ratio of A2-1 to A2-2 (A2-1: A2-2) is not particularly limited, but may be, for example, 8: 2-4: 6. the particle size distribution of the thermally conductive filler can be adjusted by classifying and mixing the thermally conductive filler. The average particle diameter in the present embodiment is D50 (median particle diameter).

The content of the thermally conductive filler is preferably 400 to 1000 parts by mass, more preferably 470 to 930 parts by mass, and still more preferably 550 to 850 parts by mass, based on 100 parts by mass of the component a 1. The content of the thermally conductive filler is 400 parts by mass or more based on 100 parts by mass of the a1 component, and the thermal conductivity of the resulting cured product is further improved, and 1000 parts by mass or less based on 100 parts by mass of the a1 component, the decrease in fluidity can be more effectively suppressed, the coatability can be ensured, and the decrease in shear displacement of the cured product can be more effectively suppressed.

(A3 component: silica powder)

The silica powder is a component for effectively suppressing dripping when a mixture obtained by mixing the first agent and the second agent of the present embodiment is applied and the coated surface is made vertical. Examples of the silica powder include silica powders such as fumed silica and precipitated silica. The surface of the silica powder may be untreated or may be hydrophobized with an organosilicon compound such as alkoxysilane, chlorosilane, or silazane, but the untreated silica powder is preferably used from the viewpoint of effectively suppressing the increase in viscosity. The specific surface area of the silica powder may be, for example, 90 to 360m²/g。

The content of the silica powder is preferably 0.2 to 2.0 parts by mass, more preferably 0.25 to 1.5 parts by mass, and still more preferably 0.4 to 1.2 parts by mass, based on 100 parts by mass of the component a 1. When the content of the silica powder is 0.2 parts by mass or more based on 100 parts by mass of the a1 component, the resultant mixture can be effectively prevented from dripping when applied and the application surface is made vertical, and when the content is 2.0 parts by mass or less, the increase in viscosity and the decrease in fluidity of the resultant mixture can be effectively prevented, the applicability can be improved, and the shear displacement and the decrease in elongation at break of the cured product can be more effectively prevented.

(A4 component: platinum catalyst)

The platinum catalyst is a component for accelerating an addition reaction between the vinyl group in the component A1 and the hydrosilyl group in the component B2 described below. The platinum catalyst may be elemental platinum or a platinum compound. Examples of the platinum compound include chloroplatinic acid, platinum-olefin complexes, platinum-alcohol complexes, and platinum coordination compounds.

The content of the platinum catalyst is preferably 0.1 to 500ppm based on 100 parts by mass of the component A1. If the content of the platinum catalyst is within the above range, the effect as a catalyst can be sufficiently obtained.

The first agent of the present embodiment may further contain additives such as organic silane and coloring agent, if necessary, in addition to the components a1 to a 4.

The organosilane is an additive for improving the wettability of the thermally conductive filler with the organopolysiloxane, and the organosilane represented by the following general formula (a5) is preferably used.

R¹ _aR² _bSi(OR³)_4－(a+b) (a5)

In the formula (a5), R¹The alkyl group has 1 to 15 carbon atoms, and examples thereof include methyl, ethyl, propyl, hexyl, nonyl, decyl, dodecyl, and tetradecyl. R¹Preferably an alkyl group having 6 to 12 carbon atoms. R²Examples of the monovalent hydrocarbon group include saturated or unsaturated monovalent hydrocarbon groups having 1 to 8 carbon atoms, such as cyclohexyl groups including cyclopentyl and cyclohexyl, alkenyl groups including vinyl and allyl groups, aryl groups including phenyl and tolyl groups, aralkyl groups including 2-phenylethyl and 2-methyl-2-phenylethyl groups, halogenated hydrocarbon groups including 3,3, 3-trifluoropropyl, 2- (perfluorobutyl) ethyl, 2- (perfluorooctyl) ethyl, and p-chlorophenyl groups. R³Is 1 or 2 or more alkyl groups having 1 to 6 carbon atoms such as methyl, ethyl, propyl, butyl, pentyl, hexyl, etc., preferably methyl or ethyl. a is an integer of 1 to 3, preferably 1. b is an integer of 0 to 2, preferably 0. a + b is an integer of 1 to 3, preferably 1.

The content of the organosilane is preferably 0.01 to 30 parts by mass, more preferably 0.1 to 5.0 parts by mass, based on 100 parts by mass of the component A1. When the content of the organosilane is in the above range, the wettability can be effectively improved.

The content of the colorant is not particularly limited, and is, for example, 0.05 to 0.2 part by mass relative to 100 parts by mass of the total of the first agent and the second agent described below.

The first agent of the present embodiment had a shear rate of 10s at 25 ℃^－1The viscosity at room temperature is 20 to 150 pas, preferably 50 to 120 pas. If the viscosity is 20 pas or more, the dripping can be suppressed even in the use in a vertical manner, and if the viscosity is 150 pas or less, the fluidity can be secured when the first agent and the second agent described below are mixed and when the mixed liquid is applied.

The first agent has a shear rate of 10s at 25 deg.C^－1The viscosity of the oil-based oil can be measured by using a rotary rheometer "HANKE MARSIII" manufactured by Thermo Fisher Scientific, Inc. More specifically, diameters may be usedAt a shear rate of 10s at a spacing of 0.5mm, a temperature of 25 DEG C^－1Under the conditions of (1).

< second agent >

The second agent contains a specific organopolysiloxane (component B1), a thermally conductive filler (component B2), a silica powder (component B3), and a specific polydimethylsiloxane (component B4).

(component B1: organopolysiloxane)

The organopolysiloxane as the component B1 is the same as the organopolysiloxane as the component A1 described above, and a repetitive description thereof will be omitted here. The organopolysiloxane that is the component B1 and the organopolysiloxane that is the component a1 may be the same type of organopolysiloxane or different types of organopolysiloxanes.

(B2 component: thermally conductive Filler)

The thermally conductive filler as the B2 component is the same as the thermally conductive filler as the a2 component described above, and the overlapping description thereof is omitted here. The thermally conductive filler of the B2 component and the thermally conductive filler of the a2 component may be the same material or different materials.

The content of the thermally conductive filler is preferably 400 to 1000 parts by mass, more preferably 470 to 930 parts by mass, and still more preferably 550 to 850 parts by mass, based on 100 parts by mass of the total of the above-mentioned component B1 and the below-mentioned component B4. The content of the thermally conductive filler is 400 parts by mass or more based on 100 parts by mass of the total of the components B1 and B4, and the thermal conductivity of the resulting cured product is further improved, and 1000 parts by mass or less is capable of more effectively suppressing a decrease in fluidity, ensuring coatability, and more effectively suppressing a decrease in shear displacement of the cured product.

(B3 ingredient: silica powder)

The silica powder as the component B3 is the same as the silica powder as the component A3, and a repetitive description thereof will be omitted here. The silica powder as the B3 component and the silica powder as the A3 component may be the same kind of material or different kinds of materials.

The content of the silica powder is preferably 0.2 to 2.0 parts by mass, more preferably 0.25 to 1.5 parts by mass, and still more preferably 0.4 to 1.2 parts by mass, based on 100 parts by mass of the total of the above-mentioned component B1 and the below-mentioned component B4. The content of the silica powder is 0.2 parts by mass or more based on 100 parts by mass of the total of the components B1 and B4, and is effective in suppressing dripping when the mixture obtained is applied so as to make the application surface vertical, and is 2.0 parts by mass or less, and is effective in suppressing an increase in viscosity and a decrease in fluidity of the mixture obtained, and is capable of improving the applicability and further effectively suppressing a shear displacement and a decrease in elongation at break of the cured product.

(component B4: polydimethylsiloxane)

The polydimethylsiloxane in the present embodiment has a hydrosilyl group (H — Si group) at least at the terminal or side chain. The hydrosilyl group reacts with the vinyl group in the a1 component and the B1 component by the action of the a4 component in the first agent to provide a crosslinked cured product having a three-dimensional network structure containing a crosslinking bond. In general, a polydimethylsiloxane having a hydrosilyl group is a substance in which a part of R of Si-R moiety in the molecule of the polydimethylsiloxane becomes a hydrogen atom. Such a polydimethylsiloxane may have a structural unit represented by the following general formula (b 4-1) or a terminal structure represented by the general formula (b 4-2). The polydimethylsiloxane may have, for example, a structural unit represented by the general formula (b 4-1) or a structural unit represented by the general formula (b 4-3), or may have a terminal structure represented by the general formula (b 4-2) or a structural unit represented by the general formula (b 4-3). The polydimethylsiloxane of the present embodiment is not limited to polydimethylsiloxane having such a structural unit or a terminal structure, and may have 2 or more or 3 or more hydrosilyl groups at a terminal or a side chain, for example.

[ chemical formula 2]

The content of the hydrosilyl group in the polydimethylsiloxane is preferably 0.01 to 15 mol%, and more preferably 0.01 to 10 mol%. The "content of hydrosilyl groups" in the present invention means the mol% of the siloxane structural units containing hydrosilyl groups, based on 100 mol% of the total structural units constituting the polydimethylsiloxane. Wherein the content of the hydrosilyl group is a value assuming that the hydrosilyl group is 1 with respect to 1 hydrosilyl group-containing siloxane structural unit.

The content of the hydrosilyl group was measured by the following method.

The content of hydrosilyl groups was determined by NMR. Specifically, the measurement was carried out by dissolving polydimethylsiloxane having hydrosilyl groups in deuterated chloroform as a deuterated solvent by ECP-300 NMR (JEOL corporation). The content of the hydrosilyl group was determined as the ratio of the hydrosilyl group to 100 mol% (vinyl group + hydrosilyl group + Si-methyl group).

The polydimethylsiloxane of the present embodiment may have either a linear structure or a branched structure, but preferably has a branched structure. By using polydimethylsiloxane having a branched structure, the viscosity before curing is low, the viscosity is not excessively high even if the thermally conductive filler is filled, the coating property is excellent, and high shear displacement and elongation at break can be achieved after curing.

Poly (dimethyl)Whether or not the siloxane has a branched structure can be determined as follows: by using a nuclear magnetic resonance apparatus AVANCEIII-500 (trade name) manufactured by BRUKER²⁹Si-NMR measurement was performed to examine the presence or absence of peaks of-55 to-66 ppm or-100 to-110 ppm as chemical shifts derived from a branched structure.

The polydimethylsiloxane of the present embodiment preferably has a viscosity of 10 to 1000 mPas at 25 ℃. When the viscosity of the polydimethylsiloxane is 10 mPas or more at 25 ℃, the shear displacement and elongation at break of a cured product to be described later can be sufficiently ensured, and the reliability against vibration or the like when the polydimethylsiloxane is mounted on an electronic component can be more effectively improved. Further, if the viscosity of polydimethylsiloxane at 25 ℃ is 1000mPa · s or less, the viscosity will not become too high when the thermally conductive filler is filled, and the coatability and the adhesion to the heat generating component can be sufficiently ensured. From this viewpoint, the viscosity of the polydimethylsiloxane at 25 ℃ is more preferably 20 to 500 mPas, and still more preferably 20 to 300 mPas.

The viscosity of polydimethylsiloxane at 25 ℃ can be measured by using a digital viscometer "DV-1" manufactured by BROOKFIELD. Using the RV spindle set, a rotor No.1 was used, and a container which was placed in the rotor and in which polydimethylsiloxane up to the reference line was able to be charged was used, and the rotor was immersed in polydimethylsiloxane, and the viscosity was measured at 25 ℃ at a rotation number of 10 rpm.

The content ratio of the polydimethylsiloxane to the component B1 in the second agent can be appropriately set according to the content of the vinyl group in the component B1 and the content of the hydrosilyl group in the component B4, and for example, the content of the vinyl group/the content of the hydrosilyl group is 50/1 to 1/1.2. When the vinyl group content and the hydrosilyl group content are within the above ranges, a crosslinked structure necessary for gelation can be sufficiently formed, and the heat resistance of a cured product can be ensured.

The second agent of the present embodiment may further contain additives such as organic silane and coloring agent, if necessary, in addition to the components B1 to B4.

The second agent of the present embodiment has a shear rate of 10s at 25 ℃^－1The viscosity of the emulsion is 20-150 Pa ·s is preferably 50 to 120 pas. If the viscosity is 20Pa · s or more, dripping can be suppressed even in the use in a vertical manner, and if the viscosity is 150Pa · s or less, fluidity can be secured when the first agent and the second agent are mixed and when the mixed liquid is applied.

The second agent has a shear rate of 10s at 25 deg.C^－1The viscosity of (b) was measured by using a rotary rheometer "HANKE MARSIII" manufactured by seimer femtoli technologies. More specifically, diameters may be usedAt a spacing of 0.5mm, a temperature of 25 ℃ and a shear rate of 10s^－1Under the conditions of (1).

[ thermally conductive cured product ]

The thermally conductive cured product in the present embodiment can be obtained by, for example, mixing the first agent and the second agent in the above-described combination of the two-pack curable composition. More specifically, the thermally conductive cured product (crosslinked cured product) was obtained as follows: in the mixture obtained by mixing the first agent and the second agent, an addition reaction between vinyl groups in the a1 component contained in the first agent and the B1 component contained in the second agent and hydrosilyl groups in the B4 component contained in the second agent proceeds by the action of the a4 component contained in the first agent, and a three-dimensional network structure having a crosslinking bond is formed. The thermally conductive cured product may be molded into a desired shape after the mixing.

The mixing is carried out using a mixing machine such as a roll mill, a kneader, or a banbury mixer, and examples thereof include a method of kneading using a universal mixer, a mixer, or Trimix (manufactured by upholstered industries). The molding method is preferably a doctor blade method, but depending on the viscosity of the resin, an extrusion method, a pressing method, a roll (calender roll) method, or the like can be used. The reaction conditions for the addition reaction are not particularly limited, but the addition reaction is usually carried out at room temperature (e.g., 25 ℃) to 150 ℃ for 0.1 to 24 hours.

The mixing ratio of the first agent and the second agent may be appropriately set depending on the kind of the first agent and the second agent used and the purpose of use, but for example, the ratio of the first agent to the second agent may be set as follows: second agent ═ 1.5: 1.0-1.0: 1.5, can also be 1: 1.

the thermally conductive cured product is a cured product having high thermal conductivity, and has a thermal conductivity of 1.0W/mK or more, or 1.5W/mK or more, for example. The upper limit of the thermal conductivity of the thermally conductive cured product is not particularly limited, but may be, for example, 3.0W/mK or less.

[ electronic apparatus ]

Fig. 1 is a schematic sectional view showing one embodiment of an electronic apparatus. As shown in fig. 1, an electronic apparatus 1 according to the present embodiment includes an electronic component 2, a thermally conductive cured product 3 according to the present embodiment, and a case 4 housing the electronic component 2 and the thermally conductive cured product 3, and the electronic component 2 and the case 4 are in contact with each other via the thermally conductive cured product 3 in the electronic apparatus 1.

The electronic component 2 may be an LSI (large scale integrated circuit), an IC (integrated circuit), a semiconductor package, or the like, and may have a structure in which battery cells 5 and conductive layers 6 are alternately stacked, as shown in fig. 1, for example. The conductive layer 6 may be formed of a metal foil or a metal mesh. The metal constituting the metal foil or the metal mesh includes, for example, at least one selected from the group consisting of aluminum, copper, silver, and gold. The metal foil may be an aluminum foil, a copper foil, a silver foil or a gold foil, and an aluminum foil is preferable from the viewpoint of obtaining a desired specific gravity.

The case 4 is, for example, a hollow substantially rectangular parallelepiped case. The case 4 may be made of metal such as GA steel plate or may be made of resin.

The electronic component 2 and the case 4 are connected via a thermally conductive cured material 3. As shown in fig. 1, in the case of an electronic component 2 having a structure in which battery cells 5 and conductive layers 6 are alternately laminated, the conductive layers 6 and the case 4 in the electronic component 2 may be connected to each other through a thermally conductive cured material 3. This allows heat generated by the electronic component 2 to be released to the outside through the case 4.

In the electronic apparatus 1 of the present embodiment, the thermally conductive cured product 3 may be disposed so as to contact the inner wall surface 4a of the case 4. The thermally conductive cured product 3 is obtained from a combination of the two-pack curable composition of the present embodiment described above, and therefore can suppress dripping even in applications in which the composition is used in a vertical position.

The thickness of the thermally conductive cured product 3 is not particularly limited, and may be, for example, 0.2mm or more from the viewpoint of shear displacement and may be, for example, 3.0mm or less from the viewpoint of heat release.

Examples

The present invention will be described in more detail below with reference to examples, but the present invention is not limited to the following examples.

[ first dose ]

First doses a1 to a10 were prepared by mixing the following components a1 to a4 at the mixing ratios (parts by mass) shown in table 1.

< A1 component: organopolysiloxane

A1-1: polydimethylsiloxane having a branched structure and having a vinyl group, a viscosity at 25 ℃ of 50 mPas, and a vinyl group content of 5.0 mol%

A1-2: polydimethylsiloxane having a branched structure and having a vinyl group, a viscosity at 25 ℃ of 120 mPas, and a vinyl group content of 2.5 mol%

A1-3: polydimethylsiloxane having a branched structure and having a vinyl group, a viscosity at 25 ℃ of 500 mPas, and a vinyl group content of 1.1 mol%

A1-4: polydimethylsiloxane having a branched structure and having a vinyl group, a viscosity of 900 mPas at 25 ℃ and a vinyl group content of 0.9 mol%

A1-5: polydimethylsiloxane having a branched structure and having a vinyl group, a viscosity of 1200 mPas at 25 ℃ and a vinyl group content of 0.8 mol%

A1-6: polydimethylsiloxane having a vinyl group and no branched structure, having a viscosity of 500 mPas at 25 ℃ and a vinyl group content of 1.1 mol%

< A2 component: thermally conductive filler

A2-1: spherical alumina having an average particle diameter of 45 μm, DAW45S (product name of Denka Co., Ltd.)

A2-2: spherical alumina having an average particle diameter of 5 μm, DAW05 (product name of Denka Co., Ltd.)

< A3 component: silica powder

A3: the specific surface area is 200m²AEROSIL200 (product name of Japan AEROSIL Co., Ltd.)

< A4 component: platinum catalyst

A4: platinum Complex polymethylvinylsiloxane solution (trade name: SILCOLEASE CATALYST 12070, manufactured by Bluestar Silicone (Bluestar Silicones))

[ Table 1]

[ second agent ]

The following B1 to B4 components were mixed in the mixing ratios (parts by mass) shown in table 2 to prepare second agents B1 to B10.

< B1 component: organopolysiloxane

B1-1: polydimethylsiloxane having a branched structure and having a vinyl group, a viscosity at 25 ℃ of 50 mPas, and a vinyl group content of 5.0 mol%

B1-2: polydimethylsiloxane having a branched structure and having a vinyl group, a viscosity at 25 ℃ of 120 mPas, a vinyl content: 2.5 mol%

B1-3: polydimethylsiloxane having a branched structure and having a vinyl group, a viscosity at 25 ℃ of 500 mPas, and a vinyl group content of 1.1 mol%

B1-4: polydimethylsiloxane having a branched structure and having a vinyl group, a viscosity of 900 mPas at 25 ℃ and a vinyl group content of 0.9 mol%

B1-5: polydimethylsiloxane having a branched structure and having a vinyl group, a viscosity of 1200 mPas at 25 ℃ and a vinyl group content of 0.8 mol%

B1-6: polydimethylsiloxane having a vinyl group and no branched structure, having a viscosity of 500 mPas at 25 ℃ and a vinyl group content of 1.1 mol%

< B2 component: thermally conductive filler

B2-1: spherical alumina having an average particle diameter of 45 μm, DAW45S (product name of Denka Co., Ltd.)

B2-2: spherical alumina having an average particle diameter of 5 μm, DAW05 (product name of Denka Co., Ltd.)

< B3 component: silica powder

B3: the specific surface area is 200m²AEROSIL200 (product name of Japan AEROSIL Co., Ltd.)

< B4 component: polydimethylsiloxane

B4: polydimethylsiloxane having hydrosilyl groups and having a viscosity of 30 mPas at 25 DEG C

[ Table 2]

The presence or absence of a branched structure in the a1 component, the B1 component, and the B4 component was determined as follows: by using a nuclear magnetic resonance apparatus AVANCEIII-500 (trade name) manufactured by BRUKER²⁹Si-NMR measurement was carried out to examine the presence or absence of peaks of-55 to-66 ppm or-100 to-110 ppm as chemical shifts derived from a branched structure.

The viscosities of the A1 component, the B1 component and the B4 component were measured using a digital viscometer DV-1 (trade name) manufactured by BROOKFIELD. Specifically, the viscosity was measured at 25 ℃ at a rotation speed of 10rpm by immersing a rotor into the evaluation sample using an RV spindle set and a rotor No.1 and using a container which can be put in the rotor and can hold the evaluation sample up to the reference line.

The average particle diameter of the thermally conductive filler was measured using a laser diffraction particle size distribution measuring apparatus SALD-20 (trade name) manufactured by Shimadzu corporation. For the evaluation sample, 50ml of pure water and 5g of the thermally conductive filler powder to be measured were added to a glass beaker, stirred with a spatula, and then subjected to a dispersion treatment for 10 minutes with an ultrasonic cleaner. The solution of the thermally conductive filler powder subjected to the dispersion treatment was added dropwise to the sample introduction part of the apparatus using a pipette, and the measurement was performed at a timing when the absorbance was stable. In the laser diffraction particle size distribution measuring apparatus, the particle size distribution is calculated from data of the light intensity distribution of diffracted/scattered light by particles detected by a sensor. The average particle diameter is determined by multiplying the value of the measured particle diameter by the relative particle amount (difference%), and dividing by the total of the relative particle amounts (100%). The average particle diameter is an average diameter of particles, and can be determined as a cumulative weight average D50 (median diameter). D50 is the particle size with the largest frequency.

The first and second agents have shear rate of 10s at 25 deg.C^－1The viscosity was measured by using a rotary rheometer "HANKE MARSIII" manufactured by Saimer Feishell science and technology. In particular, the diameter is usedAt a shear rate of 10s at a gap of 0.5mm, a temperature of 25 ℃ and a shear rate of^－1Under the conditions of (1).

[ thermally conductive cured product ]

The first dose and the second dose obtained above were used in the combinations shown in tables 3 and 4, and the ratio of 1: 1 to obtain a mixture. The resultant mixture was kept at 25 ℃ for 24 hours to carry out a curing reaction, thereby obtaining a thermally conductive cured product. Each evaluation on the thermally conductive cured product was performed by the following method. The evaluation results are shown in tables 3 and 4.

< thermal conductivity >

The thermal conductivity of the thermally conductive cured product was measured by a method in accordance with ASTM D5470 using a resin material thermal resistance measuring apparatus manufactured by Hitachi Technologies, Ltd. Specifically, the first and second doses are administered in a ratio of 1: 1 to a thickness of 0.2mm, 0.5mm and 1.0mm, and the resultant moldings were held at 25 ℃ for 24 hours to allow the curing reaction to proceed, thereby obtaining a thermally conductive cured product. The thermal resistance values of the obtained thermally conductive cured products were measured in a measurement area of 10mm × 10 mm. The slope of a straight line obtained with the thermal resistance value as the vertical axis and the thickness of the thermally conductive cured product as the horizontal axis was calculated as the thermal conductivity of the thermally conductive cured product.

< dripping >

The dropping property of the thermally conductive cured product was evaluated by the test methods shown in fig. 2 and 3. First, as shown in fig. 2, spacers 11 having a thickness of 2mm were provided at four corners of a 80mm × 80mm glass plate 10, and a mixture 12 was applied in a circular shape to a substantially central portion of the glass plate 10, the mixture 12 being prepared by mixing a first agent and a second agent in a ratio of 1: 1 by volume ratio, and sandwiched between 80mm × 80mm glass plates 13. The amount of the mixture 12 applied was such that the size of the circular shape of the mixture formed when the mixture was sandwiched between the glass plates 10 and 13 becameThe amount of (c). Then, as shown in FIG. 3, the glass plates 10 and 13 were fixed by clips 14, left standing vertically, and after standing at 25 ℃ for 24 hours, the heat conductive cured product was observed to be deviated from the initial position, thereby evaluating the dripping property. The evaluation of the dripping property was performed based on the following criteria.

A: after 24 hours, the thermally conductive cured product did not drip.

B: after 24 hours, the thermally conductive cured product dropped.

< shear Displacement >

The shear displacement of the thermally conductive cured product was measured in accordance with JIS K6850. Specifically, a mixture obtained by mixing the first agent and the second agent at a volume ratio of 1: 1 was sandwiched between an aluminum plate of 25mm × 100mm × 1mmt and a hot-dip galvanized steel plate of 25mm × 100mm × 0.5mmt at 12.5mm × 25mm × 1.5mmt, and the mixture was allowed to stand at 25 ℃ for 24 hours to solidify the mixture. Then, a test was performed at a tensile rate of 50 mm/min using a "small bench-top tester EZ-LX" manufactured by Shimadzu corporation, and the displacement (mm) at the maximum value of the load was read as a shear displacement from the relationship between the displacement and the load.

< elongation at Break >

The mixture obtained by mixing the first agent and the second agent at a volume ratio of 1: 1 was sandwiched between 2 sheets of PET film, passed through a roll, molded to a thickness of 1mm, and then allowed to stand at 25 ℃ for 24 hours to cure. After curing, the sheet was punched out into a dumbbell 8 type according to the method in accordance with JIS K6251, and the elongation (%) at the time of breaking was calculated by measuring at a tensile rate of 50 mm/min.

[ Table 3]

	Example 1	Example 2	Example 3	Example 4	Example 5
						First agent	a1	a2	a3	a4	a5
Second agent	b1	b2	b3	b4	b5
						Thermal conductivity (W/mK)	2	2	2	1.4	2.9
Dripping property	A	A	A	A	A
						Shear displacement (mm)	1.0	1.3	1.8	2.1	1.0
Elongation at Break (%)	160	200	230	250	100

[ Table 4]

	Example 6	Example 7	Comparative example 1	Comparative example 2	Comparative example 3
						First agent	a6	a7	a8	a9	a10
Second agent	b6	b7	b8	b9	b10
						Thermal conductivity (W/mK)	1.9	2.1	2	2	2
Dripping property	A	A	B	※1	A
						Shear displacement (mm)	1.6	1.3	0.7	※1	0.5
Elongation at Break (%)	220	160	80	※1	70

In addition, the method is as follows: no cured product was formed, and evaluation was impossible.

Description of the symbols

1 … electronic instrument, 2 … electronic component, 3 … thermal conductive solidified material, 4 … box, 5 … battery cell, 6 … conductive layer, 10 … glass plate, 11 … gasket, 12 … mixture, 13 … glass plate, 14 … clip