Thermally conductive components and thermally conductive sheets using the same

Abstract

This invention relates to a thermally conductive composition comprising a matrix resin composed of a thermosetting resin, a curing catalyst, and thermally conductive particles. Relative to 100 parts by weight of the matrix resin, the thermally conductive particles comprise: (a) 600-1500 parts by weight of spherical alumina with an average particle size exceeding 100 μm, (b) 100-400 parts by weight of alumina with an average particle size of 1 μm or less, and (c) 500-1500 parts by weight of aluminum nitride with an average particle size of 0.8-150 μm. Furthermore, the degree of plasticity of the thermally conductive composition after defoaming before curing is 80 or less. Therefore, this invention provides a thermally conductive composition with high thermal conductivity, low plasticity, and good processability, as well as a thermally conductive sheet using the same and a method for manufacturing the same.

Description

Technical Field

[0001] The present invention relates to a thermally conductive component suitable for placement between a heat-generating part and a heat sink in an electrical / electronic component, and a thermally conductive sheet using the same, and a method for manufacturing the same. Prior Technology

[0002] In recent years, the performance of semiconductors such as CPUs has significantly improved, and the heat generated has also increased accordingly. Therefore, heat sinks are installed on electronic components that generate heat, and thermally conductive sheets are used to improve the contact between the semiconductor and the heat sink. With the miniaturization, high performance, and high integration of machines, there is a demand for flexible thermally conductive sheets with high thermal conductivity. Previously, patent documents 1-4 have disclosed examples of thermally conductive sheets. [Previous Technical Documents] [Patent Literature]

[0003] [Patent Document 1] Japanese Patent Publication No. 2021-518466 [Patent Document 2] Japanese Re-appearance No. 2020-137970 [Patent Document 3] Japanese Re-appearance No. 2018-088416 [Patent Document 4] Japanese Patent Application Publication No. 2016-216523 Summary of the Invention

[0004] [The problem that the invention aims to solve]

[0005] However, the previous thermally conductive components and the thermally conductive sheets using them had the following problems: if the thermal conductivity was increased, the plasticity of the component would be increased, reducing its processability. To address the aforementioned problems, the present invention provides a thermally conductive composition with high thermal conductivity, low plasticity, and good processability, as well as a thermally conductive sheet using the same and a method for manufacturing the same. [Technical means to solve the problem]

[0006] The thermally conductive composition of the present invention comprises a matrix resin composed of a thermosetting resin, a curing catalyst, and thermally conductive particles, wherein, relative to 100 parts by mass of the matrix resin, the thermally conductive particles comprise: (a) 600-1500 parts by weight of spherical alumina with an average particle size exceeding 100 μm; (b) 100-400 parts by weight of alumina with an average particle size of less than 1 μm. (c) 500-1500 parts by weight of aluminum nitride with an average particle size of 0.8-150 μm, and The plasticity of the above-mentioned thermally conductive components before and after defoaming is below 80.

[0007] The thermally conductive sheet of the present invention is formed by molding the above-mentioned thermally conductive components into a sheet.

[0008] The method for manufacturing the thermally conductive sheet of the present invention involves vacuum defoaming and rolling the above-mentioned thermally conductive components into a sheet, and then heating and hardening it to manufacture the thermally conductive sheet. [Effects of the Invention]

[0009] By adopting the above-described composition, the present invention provides a thermally conductive composition with high thermal conductivity, low plasticity, and good processability, as well as a thermally conductive sheet using the same. Specifically, the plasticity of the thermally conductive composition after defoaming before curing is 80 or less, and the preferred thermal conductivity is 7.3 W / m·K or more. Furthermore, in the manufacturing method of the thermally conductive sheet of the present invention, since the composition has low plasticity and good processability, continuous sheet forming is possible. Simple Explanation of the Diagram

[0010] [Figure 1] is a schematic cross-sectional view showing a method of using a thermally conductive sheet according to one embodiment of the present invention. [Figures 2A-B] are schematic diagrams illustrating a method for measuring the thermal conductivity of a sample according to one embodiment of the present invention. [Figure 3] is a photograph (magnification 100x) of the appearance of amorphous fragmented aluminum nitride used in one embodiment of the present invention. Implementation

[0011] This invention comprises a thermally conductive composition including a matrix resin, a curing catalyst, and thermally conductive particles. The matrix resin is preferably a thermosetting resin such as polysiloxane rubber, polysiloxane gel, acrylic rubber, fluororubber, epoxy resin, phenolic resin, unsaturated polyester resin, melamine resin, acrylic resin, polysiloxane resin, or fluororesin. Polysiloxane is preferred, and can be an elastomer, gel, putty, or grease. The curing system for polysiloxane can be achieved using any method such as peroxide, addition, or condensation. Polysiloxane is preferred due to its high heat resistance. Furthermore, an addition reaction type is preferred because it is non-corrosive to the surrounding environment, produces fewer byproducts outside the system, and ensures reliable deep curing.

[0012] Thermally conductive particles are added relative to 100 parts by weight of the matrix resin component as described below. (a) The spherical alumina with an average particle size exceeding 100 μm comprises 600 to 1500 parts by mass, more preferably 600 to 1400 parts by mass. The aforementioned spherical alumina preferably has an average particle size exceeding 100 μm and below 150 μm, more preferably an average particle size of 102 to 140 μm, and even more preferably 104 to 130 μm. (b) The alumina with an average particle size of less than 1 μm comprises 100 to 400 parts by weight, more preferably 150 to 350 parts by weight. The alumina preferably has an average particle size of 0.05 to 1 μm, more preferably 0.1 to 0.9 μm, and even more preferably 0.1 to 0.9 μm. The alumina may be spherical or irregularly shaped (hereinafter also referred to as "irregular"). (c) The aluminum nitride having an average particle size of 0.8 to 150 μm comprises 500 to 1500 parts by mass, more preferably 600 to 1400 parts by mass, and even more preferably 700 to 1400 parts by mass. The aluminum nitride described above preferably has an average particle size of 0.8 to 140 μm or less, more preferably 0.8 to 130 μm, and even more preferably 0.9 to 120 μm. The aluminum nitride described above is preferably in an amorphous, fragmented state.

[0013] The plasticity of the aforementioned thermally conductive components after vacuum defoaming before hardening is below 80, with a preferred plasticity of 1-80 and a more desirable plasticity of 5-70. This allows for the acquisition of thermally conductive components with low plasticity and good processability. The plasticity is determined as follows: according to JIS K 6300-3 and ISO 2007:1991, using a Wallace plastometer, at a measurement temperature of 25°C, the sample is compressed between two metal plates under a certain load (100 N) for a certain time (15 seconds). The thickness after compression (t) is divided by the thickness before compression (t0), and this value is taken as the plasticity (P0 = t / t0 × 100). The smaller the P0, the softer the material.

[0014] The thermal conductivity of the hardened material of the aforementioned thermally conductive component is preferably 7.3 W / m·K or higher, more preferably 7.3~20 W / m·K, even more preferably 7.5~17 W / m·K, and particularly preferably 8~15 W / m·K. This high thermal conductivity makes it suitable as a TIM (Thermal Interface Material).

[0015] The hardness of the hardened form of the aforementioned thermally conductive component is preferably below 50, more preferably 10 to 50, and even more preferably 15 to 45. This improves the tracking performance of the heat-generating and heat-dissipating elements (heat sinks).

[0016] Relative to 100 parts by weight of the above-mentioned matrix resin composition, it is preferable to further add 0.1 to 10 parts by weight of a silane coupling agent, more preferably 0.5 to 7 parts by weight. The silane coupling agent has the following effects: when coated on the surface of thermally conductive particles (surface treatment), it is easily filled into the matrix resin, and it prevents the curing catalyst from being adsorbed onto the thermally conductive particles, thereby preventing curing hindrance. It is useful for storage stability. The silane coupling agent includes silane compounds or their partial hydrolysates represented by R(CH3)aSi(OR')4-a (R is an unsubstituted or substituted organic group with 1 to 20 carbon atoms, R' is an alkyl group with 1 to 4 carbon atoms, and a is 0 or 1). As denoted by R(CH3)aSi(OR')... Examples of alkoxysilane compounds (hereinafter referred to as "silanes") represented by 4-a (R refers to an unsubstituted or substituted organic group having 1 to 20 carbon atoms, R' refers to an alkyl group having 1 to 4 carbon atoms, and a is 0 or 1) include methyltrimethoxysilane, ethyltrimethoxysilane, propyltrimethoxysilane, butyltrimethoxysilane, pentyltrimethoxysilane, hexyltrimethoxysilane, hexyltriethoxysilane, octyltrimethoxysilane, octyltriethoxysilane, decyltrimethoxysilane, decyltriethoxysilane, dodecyltrimethoxysilane, dodecyltriethoxysilane, hexadecyltrimethoxysilane, hexadecyltrimethoxysilane, hexadecyltriethoxysilane, octadecyltrimethoxysilane, octadecyltrimethoxysilane, and other silane compounds. The above-mentioned silane compounds may be used in one or in combination of two or more.

[0017] The aluminum nitride in (c) above is preferably in an amorphous, fragmented form. Amorphous, fragmented aluminum nitride is readily available. Figure 3 is a photograph (100x magnification) of the appearance of amorphous, fragmented aluminum nitride used in one embodiment of the present invention.

[0018] If the thermally conductive composition system of the present invention is used as a sheet for forming a thermally conductive sheet, it has high versatility and is suitable as a TIM (Transformer Inkjet). The thickness of the thermally conductive sheet is preferably in the range of 0.2 to 10 mm.

[0019] The manufacturing method of the thermally conductive sheet of the present invention involves vacuum defoaming and rolling of the above-mentioned thermally conductive components to form a sheet, followed by heating and hardening to produce the thermally conductive sheet. Vacuum defoaming involves reducing the pressure of the above-mentioned thermally conductive components (composite) to -0.08 to -0.1 Pa and allowing it to stand for approximately 5 to 10 minutes to defoam. Rolling includes processes such as rolling and pressurization; since rolling allows for continuous production, it is preferred.

[0020] The insulation breakdown voltage (JIS K6249) of the above-mentioned thermally conductive components is preferably 7~16 kV / mm. This allows for the fabrication of thermally conductive sheets with high electrical insulation properties.

[0021] The volume resistivity (JIS K6249) of the above-mentioned thermally conductive components is preferably 10¹⁰ to 10¹⁴ Ω·cm. This allows for the fabrication of thermally conductive sheets with high electrical insulation properties.

[0022] As an example of the present invention, in the case of an addition-reaction type polysiloxane composition (uncured composition), it is preferred to be a composite of the following composition. A. Matrix resin components The matrix resin composition includes (A1) and (A2) as follows. (A1) + (A2) is set at 100 parts by weight. (A1) A linear organopolysiloxane containing at least two alkenyl groups bonded to silicon atoms in one molecule. (A2) Crosslinking component: The amount of organohydrogenated polysiloxane containing at least two hydrogen atoms bonded to silicon atoms per molecule is less than 1 mole relative to the 1 mole of alkenyl groups bonded to silicon atoms in component A above. In addition to the components (A1) and (A2) mentioned above, it may also contain organic polysiloxanes that do not have reactive groups. B Thermally conductive particles The thermally conductive particles are configured as follows relative to 100 parts by weight of the matrix resin. (a) Spherical alumina with an average particle size exceeding 100 μm, comprising 600-1500 parts by weight. (b) Alumina with an average particle size of less than 1 μm is 100~400 parts by weight. (c) 500-1500 parts by weight of aluminum nitride with an average particle size of 0.8-150 μm. C. Platinum group metal catalysts: relative to the matrix resin composition, in units of mass, the amount is 0.01~1000 ppm. D Other additives: curing delay agents, colorants, etc.; any amount of silane coupling agent.

[0023] The following is a description of each component. (1) Basic polymer components (A1 component) The basic polymer component is an organopolysiloxane containing two or more alkenyl groups bonded to silicon atoms per molecule. This organopolysiloxane containing two or more alkenyl groups is the main agent (basic polymer component) in the polysiloxane rubber composition of this invention. This organopolysiloxane has two alkenyl groups bonded to silicon atoms per molecule; the alkenyl groups are vinyl, allyl, etc., with 2 to 8 carbon atoms, particularly 2 to 6. In terms of workability and hardenability, the ideal viscosity is 10 to 1,000,000 mPa·s at 25°C, particularly 100 to 100,000 mPa·s. Specifically, an organopolysiloxane, represented by the following general formula (Chemical 1), containing two or more alkenyl groups bonded to the silicon atoms at the ends of the molecular chain, is used. The side chains are linear organopolysiloxanes with alkyl ends. Ideally, the viscosity at 25°C should be 10–1,000,000 mPa·s, considering workability and hardenability. Furthermore, this linear organopolysiloxane may also contain a small amount of branched structures (trifunctional siloxane units) in its molecular chain.

[0024] (Chemistry 1)

[0025] In the formula, R1 refers to an unsubstituted or substituted monovalent hydrocarbon group that is the same or different from each other and does not have an aliphatic unsaturated bond, R2 refers to an alkenyl group, and k is 0 or a positive integer. Here, the unsubstituted or substituted monovalent hydrocarbon group that does not have an aliphatic unsaturated bond as R1 is preferably one with 1 to 10 carbon atoms, especially 1 to 6. Specifically, examples include: alkyl groups such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tributyl, pentyl, neopentyl, hexyl, cyclohexyl, octyl, nonyl, decyl, etc.; aryl groups such as phenyl, tolyl, xylyl, naphthyl, etc.; aralkyl groups such as benzyl, phenethyl, phenylpropyl, etc.; and those formed by substituting one or all of the hydrogen atoms of these groups with halogen atoms such as fluorine, bromine, chlorine, or cyano, such as chloromethyl, chloropropyl, bromoethyl, trifluoropropyl, etc., cyanoethyl, etc. As for the alkenyl group of R2, it is preferred to have 2 to 6 carbon atoms, especially 2 to 3. Specifically, examples include vinyl, allyl, propenyl, isopropenyl, butenyl, isobutenyl, hexenyl, cyclohexenyl, etc., with vinyl being preferred. In general formula (1), k is usually a 0 or positive integer satisfying 0 ≤ k ≤ 10000, preferably an integer satisfying 5 ≤ k ≤ 2000, and more preferably an integer satisfying 10 ≤ k ≤ 1200.

[0026] The organopolysiloxane as component A1 can be used in organopolysiloxanes having three or more alkenyl groups in one molecule, typically 3 to 30, preferably around 3 to 20, such as vinyl or allyl groups, with 2 to 8 carbon atoms, particularly 2 to 6, bonded to silicon atoms. The molecular structure can be any of the following: linear, cyclic, branched, or three-dimensional network. Preferably, it is a linear organopolysiloxane with a main chain composed of repeating two organopolysiloxane units, the ends of the molecular chain capped by three organosilyloxy groups, and a viscosity at 25°C of 10 to 1,000,000 mPa·s, particularly 100 to 100,000 mPa·s.

[0027] Alkenes can be bonded to any part of the molecule. For example, they can include silicon atoms bonded to the ends of the molecular chain or to non-ends (the middle of the molecular chain). Among them, the linear organopolysiloxane represented by the following general formula (Chemical 2) has 1 to 3 alkenes on the silicon atoms at both ends of the molecular chain (wherein, if the total number of alkenes bonded to the silicon atoms at the ends of the molecular chain is less than 3, they are alkenes bonded to silicon atoms at non-ends (the middle of the molecular chain)). For example, a linear organopolysiloxane having at least one substituent as a substituent in a diorganopolysiloxane unit, and as mentioned above, having a viscosity of 10 to 1,000,000 mPa·s at 25°C in terms of workability and hardening properties is more ideal. Furthermore, the linear organopolysiloxane can also contain a small amount of branched structures (trifunctional siloxane units) in its molecular chain.

[0028] (Chemistry 2)

[0029] In the formula, R3 represents unsubstituted or substituted monovalent hydrocarbon groups which are the same as or different from each other, and at least one of them is an alkenyl group. R4 represents unsubstituted or substituted monovalent hydrocarbon groups which are the same as or different from each other and do not have aliphatic unsaturated bonds. R5 represents an alkenyl group, and l and m are 0 or positive integers. Here, as the monovalent hydrocarbon group of R3, those having 1 to 10 carbon atoms, particularly 1 to 6 carbon atoms, are preferred. Specifically, examples include alkyl groups such as methyl, ethyl, propyl, isopropyl, butyl, isobutyl, tert-butyl, pentyl, neopentyl, hexyl, cyclohexyl, octyl, nonyl, and decyl; aryl groups such as phenyl, tolyl, xylyl, and naphthyl; aralkyl groups such as benzyl, phenethyl, and phenylpropyl; alkenyl groups such as vinyl, allyl, propenyl, isopropenyl, butenyl, hexenyl, cyclohexenyl, and octenyl; or those obtained by substituting a part or all of the hydrogen atoms of these groups with halogen atoms such as fluorine, bromine, and chlorine, or cyano groups, such as chloromethyl, chloropropyl, bromoethyl, trifluoropropyl, and other halogen-substituted alkyl groups or cyanoethyl. Further, as the monovalent hydrocarbon group of R4, those having 1 to 10 carbon atoms, particularly 1 to 6 carbon atoms, are also preferred, and examples include the same ones as the specific examples of R1 above, but do not include alkenyl groups. As the alkenyl group of R5, for example, those having 2 to 6 carbon atoms, particularly 2 to 3 carbon atoms, are preferred, and specifically, examples include the same ones as R2 in the above formula (Chemical Formula 1), and vinyl is preferred. l and m are usually 0 or positive integers satisfying 0 < l + m ≤ 10000, preferably integers satisfying 5 ≤ l + m ≤ 2000, more preferably integers satisfying 10 ≤ l + m ≤ 1200 and 0 < l / (l + m) ≤ 0.2, and preferably integers satisfying 0.0011 ≤ l / (l + m) ≤ 0.1.

[0030] (2) Crosslinking component (Component A2) The organohydrogenpolysiloxane of Component A2 of the present invention functions as a crosslinking agent, and a cured product is formed by an addition reaction (hydrosilylation) of the SiH group in this component and the alkenyl group in Component A. Any organohydrogenpolysiloxane can be used as long as it has two or more hydrogen atoms bonded to silicon atoms (i.e., SiH groups) in one molecule. The molecular structure of the organohydrogenpolysiloxane can be any one of linear, cyclic, branched, and three-dimensional network structures, and those having the number of silicon atoms (i.e., degree of polymerization) in one molecule of 2 to 1000, particularly about 2 to 300, can be used.

[0031] The position of the silicon atom to which the hydrogen atom is bonded is not particularly limited, and it can be either at the end of the molecular chain or in the middle of the molecular chain (non-terminal of the molecular chain). Further, as the organic group bonded to the silicon atom other than the hydrogen atom, examples include unsubstituted or substituted monovalent hydrocarbon groups having no aliphatic unsaturated bond and the same as R1 in the above general formula (Chemical Formula 1).

[0032] Examples of organic hydrogenated polysiloxanes as components A2 include those with the following structures. (Chemistry 3)

[0033] In the above formula, R6 refers to alkyl, phenyl, epoxy, acrylonitrile, methacrylonitrile, alkoxy, and hydrogen atoms that are the same or different from each other, of which at least two are hydrogen atoms. L is an integer from 0 to 1,000, especially from 0 to 300, and M is an integer from 1 to 200.

[0034] (3) Catalyst component (component C) The catalyst component of component C can be any catalyst used in the hydrosiliconization reaction. Examples include: platinum black; platinum chloride; chloroplatinic acid; reactants of chloroplatinic acid with monohydric alcohols; complexes of chloroplatinic acid with alkenes or vinyl siloxanes; platinum group metal catalysts such as diacetyl acetate platinum, palladium catalysts, and rhodium catalysts.

[0035] (4) Thermally conductive particles (component B) Compared to 100 parts by mass of component A as the matrix component, component B preferably contains a total of 1,200 to 3,400 parts by mass of thermally conductive particles. This helps to maintain a higher thermal conductivity.

[0036] In this invention, thermally conductive particles are made from three or more types of inorganic particles with different average particle sizes. This allows for the embedding of small-diameter thermally conductive inorganic particles between larger particles, achieving a near-dense filling state and thereby improving thermal conductivity.

[0037] (5) Other additives Other components besides those mentioned above may be added to the composition of this invention as needed. For example, heat-resistant enhancers such as iron oxide, titanium dioxide, and cerium oxide, flame retardants, and curing delay agents may be added. Organic or inorganic pigments may also be added for coloring and tinting. The aforementioned silane coupling agents may also be added.

[0038] The following figures are used for illustration. In the following figures, the same symbols represent the same objects. Figure 1 is a schematic cross-sectional view of a thermally conductive sheet assembled into a heat dissipation structure 10 according to one embodiment of the present invention. The thermally conductive sheet 11b is used to dissipate heat emitted by electronic components 13 such as semiconductor elements. It is fixed to the main surface 12a of the heat sink 12 facing the electronic component 13 and is sandwiched between the electronic component 13 and the heat sink 12. Furthermore, the thermally conductive sheet 11a is sandwiched between the heat sink 12 and the heat sink 15. Moreover, the thermally conductive sheets 11a and 11b together with the heat sink 12 constitute a heat dissipation member for dissipating heat from the electronic component 13. The heat sink 12 is formed, for example, in the shape of a square plate, having a main surface 12a facing the electronic component 13 and sidewalls 12b erected along the outer periphery of the main surface 12a. In the heat sink 12, a heat conduction sheet 11b is provided on the main surface 12a surrounded by the side wall 12b, and a heat sink 15 is provided on the other side 12c opposite to the main surface 12a, insulated from the heat conduction sheet 11a. Electronic components 13, such as semiconductor devices like BGAs, are mounted to the wiring board 14. [Example]

[0039] The invention is illustrated using the following examples. However, the invention is not limited to these examples. Various parameters were measured using the methods described below.

[0040] Thermal conductivity The thermal conductivity of the polysiloxane rubber sheet was measured using a Hot Disk (according to ISO / CD 22007-2). As shown in Figure 2A, the thermal conductivity measuring device 1 consists of a sensor 2 made of polyimide film sandwiched between two samples 3a and 3b. A constant power is applied to the sensor 2 to generate a certain amount of heat, and the thermal characteristics are analyzed based on the temperature rise of the sensor 2. The diameter of the front end 4 of the sensor 2 is 7 mm, as shown in Figure 2B, forming a double-helix electrode structure. The lower part is equipped with an electrode 5 for applying current and an electrode 6 for measuring resistance (temperature measurement). The thermal conductivity is calculated using the following formula (Equation 1). (Equation 1) λ: Thermal conductivity (W / m·K) P0: Constant power (W) r: Radius of the sensor (m) τ: α: Thermal diffusivity of the sample (m² / s) t: Measurement time (s) D(τ): A dimensionless function of τ ∆T(τ): Temperature rise of the sensor (K) <Hardness> The hardness of the thermally conductive polysiloxane rubber sheet was determined according to ASKER C (ASTM D2240:2021). For reference, the hardness of SHORE 00 (JIS K 7312:1996) was also determined. <Plasticity> The degree of plasticity is determined as follows: According to JIS K 6300-3:2019 and ISO 2007:1991, using a Wallace plastometer, the sample is compressed between two metal plates at a measurement temperature of 23°C under a certain load (100 N) for a certain time (15 seconds). The thickness after compression (t) is divided by the thickness before compression (t0), and this value is taken as the degree of plasticity (P0 = t / t0 × 100). The larger the P0, the softer the material. The degree of plasticity before vacuum refers to the plasticity of the composite material in its final state. The degree of plasticity after defoaming refers to the plasticity after the composite material has been defoamed for 5 minutes under a reduced pressure of -0.1 Pa. The composite material will undergo sheet formation after defoaming, therefore the degree of plasticity after defoaming is very important.

[0041] (Examples 1-10, Comparative Examples 1-4) 1.Material composition (1) Polyorganosiloxane (Component A) The process uses a two-component, room-temperature curing polysiloxane polymer (polysiloxane component) containing a commercially available polyorganosiloxane. One liquid (liquid A) contains a base polymer component (component A1 in component A) and a platinum group metal catalyst, while the other liquid (liquid B) contains a base polymer component (component A1 in component A) and an organohydrogenated polysiloxane as a crosslinking agent component (component A2 in component A). (2) Thermally conductive particles (component B) The thermally conductive particles listed in Table 1 are used. The average particle size is the D50 (median particle size) of the cumulative particle size distribution based on volume, determined by laser diffraction / scattering. For example, the LA-950S2 laser diffraction / scattering particle distribution measuring device manufactured by Horiba Corporation is used for this measurement. The value before μm in the table is the average particle size of each particle. Also, AlN in the table is an abbreviation for aluminum nitride. (3) Platinum group metal catalysts (C component) As an additional platinum group metal catalyst, a platinum-vinyldisilazane complex is used. Furthermore, as described above, the two-component room-temperature curing polysiloxane polymer (polysiloxane component) contains a platinum group metal catalyst. When preparing the polysiloxane compositions of each embodiment, 2 parts by weight (2 g) of additional platinum group metal catalyst are added relative to 100 parts by weight (100 g) of the polysiloxane component, in a manner that allows the polyorganosiloxane to be fully cured in one step.

[0042] 2. Complex For each material, weigh the amounts shown in Table 1 above and place them in a mixing apparatus to prepare a composite. In Table 1, the amount (parts by mass) of each material is recorded when the polysiloxane component (two-component room temperature curing polysiloxane polymer) is set at 100 parts by mass (100 g). The composite was defoamed for 5 minutes under reduced pressure of -0.1 Pa.

[0043] 3. Sheet forming process The above composite was sandwiched between a release-treated polyethylene terephthalate (PET) film and rolled into a sheet with a thickness of 2.0 mm using a constant-speed roller. The sheet was then heated and cured at 100°C for 15 minutes to form a thermally conductive polysiloxane rubber sheet. The conditions and results are shown in Tables 1 and 2.

[0044] [Table 1] Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 matrix Basic polymer: A1(g) Basic polymer: A2(g) 50 50 50 50 50 50 50 50 50 50 50 50 50 50 additive Decyltrimethoxysilane (g) - - 2 2 2 2 2 catalyst Platinum catalyst (g) 2 2 2 2 2 2 2 Heat conduction (a) Spherical alumina 108 μm (g) 1200 1000 1200 1400 900 600 1000 Sex particles (b) 0.3 μm spherical alumina (g) - - - - - - - (b) Amorphous alumina 0.2 μm (g) - - - - - - - (b) Amorphous alumina 0.3 μm (g) 280 150 280 280 280 280 350 (c) Amorphous AlN 1 μm(g) 250 300 300 300 300 - - Amorphous alumina 2 μm (g) - 200 - - - 400 200 (c) Amorphous AlN 5 μm(g) 100 - - - - - - (c) Amorphous AlN 15 μm(g) - - - - - - - (c) Amorphous AlN 20 μm(g) 450 500 600 600 600 600 500 Spherical alumina, 80 μm (g) - - - - - - - (c) Amorphous AlN 80 μm(g) - - - - - - 100 (c) Amorphous AlN 108 μm(g) - - - - 300 400 100 result Thermal conductivity (W / mK) [Hot Disk] 9.6 8.8 9.7 10.5 11.0 9.7 8.6 Hardness [ASKER C] 19 30 32 35 37 31 31 Hardness [SHORE 00] 33 50 52 60 59 55 56 Plasticization degree before vacuum 27.5 32.6 33.8 42.2 52.9 49.5 43.5 Plasticization degree after defoaming 27.5 35.5 34.8 51.9 57.5 61.1 44.9

[0045] [Table 2] Example 8 Example 9 Example 10 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 matrix Basic polymer: A1(g) Basic polymer: A2(g) 50 50 50 50 50 50 50 50 50 50 50 50 50 50 additive Decyltrimethoxysilane (g) 2 2 2 2 2 2 - catalyst Platinum catalyst (g) 2 2 2 2 2 2 2 Heat conduction (a) Spherical alumina 108 μm (g) 1200 1300 1300 - 550 1000 - Sex particles (b) 0.3 μm spherical alumina (g) - - 150 - - - - (b) Amorphous alumina 0.2 μm (g) - 150 - - - - - (b) Amorphous alumina 0.3 μm (g) 280 - - 280 280 480 350 (c) Amorphous AlN 1 μm(g) 300 450 400 300 300 300 - Amorphous alumina 2 μm (g) - - - - - - 400 (c) Amorphous AlN 5 μm(g) - - - - - - - (c) Amorphous AlN 15 μm(g) 600 500 500 - - - 400 (c) Amorphous AlN 20 μm(g) - - - 600 600 600 - Spherical alumina, 80 μm (g) - - - 1200 550 - 1000 (c) Amorphous AlN 80 μm(g) - - - - - - - (c) Amorphous AlN 108 μm(g) - - - - 200 - - result Thermal conductivity (W / mK) [Hot Disk] 9.8 9.6 8.9 10.0 11.2 9.6 8.3 Hardness [ASKER C] 34 36 49 55 53 61 38 Hardness [SHORE 00] 60 60 70 73 70 75 61 Plasticization degree before vacuum 48.0 36.4 51.3 72.1 87.8 62.2 66.2 Plasticization degree after defoaming 52.1 40.6 52.2 93.6 96.7 84.0 96.1

[0046] As shown in the above embodiments, it can be confirmed that: regarding the thermally conductive particles, relative to 100 parts by mass of the above-mentioned matrix resin, the thermally conductive particles are... (a) 600-1500 parts by weight of spherical alumina with an average particle size exceeding 100 μm; (b) 100-400 parts by weight of alumina with an average particle size of less than 1 μm. (c) 500-1500 parts by weight of aluminum nitride with an average particle size of 0.8-150 μm. As a result, the thermal conductivity is high, and the plasticity of the composition is low after defoaming. In contrast, Comparative Example 1 lacked component (a), Comparative Example 2 contained component (a), but in small amounts, Comparative Example 3 contained small amounts of component (b), and Comparative Example 4 lacked component (a) and contained small amounts of component (c). Therefore, the plasticization degree of these comparative examples after defoaming was not good. [Industrial Applicability]

[0047] The thermally conductive components and thermally conductive sheets of the present invention are suitable for placement between the heat-generating parts and heat sinks of electrical / electronic components, etc.

[0048] 1: Thermal conductivity measuring device 2: Sensor 3a, 3b: Samples 4: Front end of the sensor 5: Electrodes for applying current 6: Electrodes for resistance measurement (electrodes for temperature measurement) 10: Heat dissipation structure 11a, 11b: Thermally conductive sheets 12: Heatsink 13: Electronic Components 14: Wiring board 15: Hot Exchange

Claims

1. A thermally conductive composition comprising a matrix resin composed of a thermosetting resin, a curing catalyst, and thermally conductive particles, characterized in that: the matrix resin is an addition-curing polysiloxane polymer; the thermally conductive particles, relative to 100 parts by mass of the polysiloxane polymer, comprise: (a) 600 to 1500 parts by mass of spherical alumina with an average particle size exceeding 100 μm; (b) 100 to 400 parts by mass of alumina with an average particle size of 1 μm or less; (c) 500 to 1500 parts by mass of amorphous aluminum nitride with an average particle size of 0.8 to 150 μm; and comprising: (d) an additional platinum group metal catalyst in an amount of 0.01 to 1000 ppm by mass relative to the polysiloxane polymer; and the plasticity of the composite prior to curing the thermally conductive composition, after defoaming for 5 minutes under reduced pressure of -0.1 Pa, is 80 or less.

2. As in claim 1, the thermally conductive component, wherein, The plasticity of the composite material before hardening of the above thermally conductive components, after defoaming for 5 minutes under reduced pressure of -0.1 Pa, is below 70%.

3. As in claim 1, the thermally conductive component, wherein, The thermal conductivity of the hardened form of the above-mentioned thermally conductive components is 7.3 W / m·K or higher.

4. The thermally conductive component as claimed in claim 1, wherein, The hardened form of the above-mentioned thermally conductive components has an ASKER C hardness of 50 or less.

5. The thermally conductive component as claimed in claim 1, wherein, In addition to 100 parts by weight of the above-mentioned matrix resin, 0.1 to 10 parts by weight of silane coupling agent are added.

6. A thermally conductive sheet, characterized in that: it is formed by molding the thermally conductive component of any one of claims 1 to 5 into a sheet.

7. As in request item 6, the thermally conductive sheet, wherein, The thickness of the aforementioned thermally conductive sheet is in the range of 0.2 to 10 mm.

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