Heat-conducting insulating organic silicon resin composition and preparation method thereof

Abstract

The invention relates to a heat-conducting resin composition, in particular to a heat-conducting insulating organic silicon resin composition and a preparation method thereof. The heat-conducting insulating organic silicon resin composition is prepared from, by mass, 100 parts of vinyl silicone oil, 10-20 parts of hydrogen-containing silicone oil, 30-50 parts of heat-conducting inorganic powder and 1-5 parts of multi-walled carbon nanotubes, the heat-conducting inorganic powder is surface-modified core-shell structure nanofiller, and the core-shell structure nanofiller comprises nanoparticles of an inner core and an inorganic shell layer of a surface layer. The nano-particles with high thermal conductivity are selected, the surfaces of the nano-particles are coated with the inorganic shell layer to form the high-thermal-conductivity filler with the core-shell structure, the multi-wall carbon nanotubes are used, a continuous thermal conduction network is formed in the composite material, heat is effectively transferred, the interface thermal resistance is reduced, the thermal conduction efficiency is improved, and the thermal conductivity of the composite material is improved.

Description

Technical Field

[0001] The invention relates to a thermally conductive resin composition, in particular to a thermally conductive insulating organic silicon resin composition and a preparation method thereof. Background Art

[0002] Currently, electronic devices such as smartphones require stronger temperature control capabilities due to enhanced functions and reduced component size. Their higher functional density and smaller heat dissipation space require stronger temperature control capabilities. Due to the size and space limitations inside the device, high-performance soft materials such as thermally conductive insulating silicone resin compositions are needed. With their flexibility, excellent insulation, compressibility and viscosity, they can eliminate air gaps and improve overall heat transfer capabilities to keep the device working at low temperatures.

[0003] However, most of the existing organic silicon thermal conductive materials are made of organic silicon resin compositions with thermal conductive fillers added to them. Due to the single distribution structure of the fillers and the discontinuous thermal conductive network, there are still some shortcomings, such as low thermal conductivity and poor thermal conductivity. In addition, as the trend of miniaturization and ultra-thinness of equipment intensifies, the market's requirements for thermal conductive materials are also getting higher and higher. Therefore, it is necessary to develop new thermal conductive materials with higher thermal conductivity and better adaptability. Summary of the invention

[0004] In view of the deficiencies in the prior art, the present invention aims to provide a thermally conductive and insulating silicone resin composition and a preparation method thereof.

[0005] The technical solution of the present invention to solve the above technical problems is as follows: The first aspect of the present invention is to provide a thermally conductive insulating silicone resin composition, which comprises, by mass, 100 parts of vinyl silicone oil, 10-20 parts of hydrogenated silicone oil, 30-50 parts of thermally conductive inorganic powder, and 1-5 parts of multi-walled carbon nanotubes (MWCNTs); wherein the thermally conductive inorganic powder is a surface-modified core-shell structure nanofiller, and the core-shell structure nanofiller comprises nanoparticles in the inner core and an inorganic shell layer on the surface.

[0006] Furthermore, the nanoparticles are selected from one or more of aluminum oxide (Al2O3), boron nitride (BN), silicon carbide (SiC), aluminum nitride (AlN), zinc oxide (ZnO), titanium dioxide (TiO2), and graphene, and the inorganic shell layer is aluminum silicate and / or silicon dioxide.

[0007] Furthermore, in the core-shell structure nanofiller, the nanoparticles account for 90-95% of the total mass of the core-shell structure nanofiller, and the inorganic shell layer accounts for 5-10% of the total mass of the core-shell structure nanofiller.

[0008] Furthermore, the particle size of the core-shell structured nanofiller is 100-150 nm, and the thickness of the inorganic shell layer is 5-20 nm.

[0009] The second aspect of the present invention is to provide a method for preparing the thermally conductive insulating silicone resin composition, comprising the following steps: S1. Polymer matrix mixing: vinyl silicone oil and hydrogen silicone oil are added to the heat-conducting inorganic powder suspension, stirred and dissolved evenly, multi-walled carbon nanotubes are added, and ultrasonic dispersion treatment is performed for 30 minutes to obtain a mixed solution; S2. Degassing treatment: pour the mixed solution into a vacuum degasser, and perform vacuum degassing for 10-20 minutes to remove bubbles in the mixed solution, thereby obtaining a thermally conductive insulating organic silicone resin composition.

[0010] Furthermore, the method for preparing the thermally conductive inorganic powder suspension comprises the following steps: (1) Hydroxylation treatment: the nanoparticles are mixed with sulfuric acid, stirred at 100°C for 8 h, centrifuged, washed, dried, and ground to obtain hydroxylated nanoparticles; (2) Inorganic shell coating: Add hydroxylated nanoparticles to ethanol, stir ultrasonically for 30 minutes, drop silane coupling agent, stir at 70°C for 2 hours, add aluminum hydroxide and / or silicon hydroxide, stir while ultrasonically for 0.5 hours to obtain a mixed solution; dissolve tetraethyl silicate in ethanol, add acetic acid dropwise to adjust the pH to 6.5, add the dissolved tetraethyl silicate solution dropwise to the mixed solution, add sodium hydroxide solution dropwise to adjust the pH to 9.5, stir at 110°C for 24 hours, centrifuge, wash, and dry, and heat treat the solid at 300°C for 3 hours to obtain nanoparticles with surface coated with an inorganic shell; (3) Preparation of suspension: Add the nanoparticles coated with an inorganic shell layer into ethanol, stir ultrasonically for 25 min, add a silane coupling agent dropwise, and stir at 70 °C for 2 h to obtain a thermally conductive inorganic powder suspension.

[0011] Furthermore, in step (1), the solid-liquid ratio of the nanoparticles to sulfuric acid is 1-3:40-70 g / mL, and the concentration of sulfuric acid is 30-50%; in step (2), the solid-liquid ratio of the hydroxylated nanoparticles to ethanol is 1-2:80 g / mL, and the solid-liquid ratio of the hydroxylated nanoparticles to the silane coupling agent is 1:0.01-0.1 g / mL; in step (3), the solid-liquid ratio of the nanoparticles coated with an inorganic shell layer to the silane coupling agent is 1:0.01-0.1 g / mL.

[0012] Furthermore, in step (2) and step (3), the silane coupling agent is γ-aminopropyltriethoxysilane (KH550) or γ-glycidyloxypropyltrimethoxysilane (KH560).

[0013] Furthermore, the thermally conductive inorganic powder suspension is added in a mass ratio of 1:2-5 to the mixture of the thermally conductive inorganic powder and the vinyl silicone oil and the hydrogen-containing silicone oil.

[0014] Furthermore, the step S2 further includes step S3, film preparation: placing the thermally conductive insulating silicone resin composition in a casting machine for casting, drying at 40-60° C. to completely volatilize the solvent, and obtaining a thermally conductive insulating silicone resin composition film, wherein the thickness of the thermally conductive insulating silicone resin composition film is 10-20 μm.

[0015] The beneficial effects achieved by the present invention are: 1. The present invention uses nanoparticles with high thermal conductivity, covers the surface of the nanoparticles with an inorganic shell layer to form a high thermal conductivity filler with a core-shell structure, and uses multi-walled carbon nanotubes to form a continuous thermal conductive network in the composite material, which effectively transfers heat, reduces interfacial thermal resistance, improves heat conduction efficiency, improves the thermal conductivity of the composite material, and ensures that heat can be quickly transferred from the heat source.

[0016] 2. The present invention adds multi-walled carbon nanotubes to the composite material, and utilizes its high axial thermal conductivity to form an efficient heat conduction path. The multi-walled carbon nanotubes can bridge the gaps between the thermally conductive inorganic powders to form a continuous thermally conductive network, thereby improving the overall thermal conductivity. The multi-walled carbon nanotubes also have good dispersibility, thereby preventing the thermally conductive inorganic powders from agglomerating and ensuring their uniform distribution in the silicone resin.

[0017] 3. The present invention uses a silane coupling agent to modify the surface of the thermally conductive inorganic powder to improve its interface compatibility with the silicone resin. The interface bonding force between the modified thermally conductive inorganic powder and the silicone resin is enhanced, the interface thermal resistance is reduced, and the heat conduction efficiency is improved.

[0018] 4. The present invention utilizes thermally conductive inorganic powder and multi-walled carbon nanotubes to form a continuous thermally conductive network in the silicone resin, which effectively transfers heat, reduces thermal resistance, and improves the overall thermal conductivity. The high thermal conductivity of the thermally conductive inorganic powder and multi-walled carbon nanotubes allows heat to be quickly transferred along these paths to form an efficient heat conduction system. The silane coupling agent tightly combines the thermally conductive inorganic powder and the silicone resin through chemical bonding, reduces the interface thermal resistance, and improves the thermal conduction efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a flow chart of the preparation method of the thermally conductive insulating silicone resin composition used in Examples 1-3 of the present invention. DETAILED DESCRIPTION

[0020] The technical solution of the present invention is further described below in conjunction with specific implementation methods.

[0021] Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0022] In the present invention, unless otherwise specified, all equipment and raw materials can be purchased from the market or are commonly used in the industry. The methods in the following embodiments, unless otherwise specified, are conventional methods in the art.

[0023] Example 1 A thermally conductive insulating silicone resin composition comprises, by mass, 100 parts of vinyl silicone oil, 15 parts of hydrogenated silicone oil, 38 parts of thermally conductive inorganic powder, and 3 parts of multi-walled carbon nanotubes; the thermally conductive inorganic powder is a surface-modified core-shell structure nanofiller, the core-shell structure nanofiller comprises nanoparticles (aluminum oxide) in the inner core and an inorganic shell layer (aluminum silicate and silicon dioxide) in the surface layer; and the silane coupling agent is γ-aminopropyltriethoxysilane.

[0024] A method for preparing a thermally conductive insulating silicone resin composition, such as Figure 1 As shown, the following steps are included: (1) Hydroxylation treatment: 1 g of nanoparticles was mixed with 50 mL of 30% sulfuric acid, stirred at 100 °C for 8 h, cooled, centrifuged, washed, dried, and ground to obtain hydroxylated nanoparticles; (2) Inorganic shell coating: add 1 g of hydroxylated nanoparticles to 80 mL of ethanol, stir under ultrasonication for 30 min, drop 0.05 mL of silane coupling agent, stir at 70 °C for 2 h, add 0.05 g of aluminum hydroxide and 0.05 g of silicon hydroxide, stir under ultrasonication for 0.5 h to obtain a mixed solution; 1 mL of tetraethyl silicate was dissolved in 10 mL of ethanol, acetic acid was added dropwise to adjust the pH to 6.5, the dissolved tetraethyl silicate solution was added dropwise to the mixed solution, sodium hydroxide solution was added dropwise to adjust the pH to 9.5, stirred at 110°C for 24 h, centrifuged, washed, and dried, and the solid was heat-treated at 300°C for 3 h to obtain nanoparticles with an inorganic shell layer on the surface; (3) Preparation of suspension: Add 1 g of nanoparticles coated with an inorganic shell layer into 80 mL of ethanol, stir ultrasonically for 25 min, add 0.05 mL of silane coupling agent dropwise, and stir at 70 °C for 2 h to obtain a thermally conductive inorganic powder suspension; (4) Polymer matrix mixing: vinyl silicone oil and hydrogen silicone oil are added to the heat-conducting inorganic powder suspension, stirred and dissolved evenly, multi-walled carbon nanotubes are added, and ultrasonic dispersion treatment is performed for 30 minutes to obtain a mixed solution; (5) Degassing: Pour the mixed solution into a vacuum degasser and degas for 15 minutes to remove bubbles in the mixed solution; (6) Film preparation: The mixed solution is placed in a casting machine for casting, and dried at 50°C to completely evaporate the solvent to obtain a thermally conductive insulating silicone resin composition film with a thickness of 15 μm.

[0025] (7) Curing treatment: The film obtained by casting was placed in a curing furnace and cured at 100°C for 0.5 h. After cooling to room temperature, performance testing was performed.

[0026] Example 2 A thermally conductive insulating silicone resin composition comprises, by mass, 100 parts of vinyl silicone oil, 20 parts of hydrogenated silicone oil, 40 parts of thermally conductive inorganic powder, and 5 parts of multi-walled carbon nanotubes; the thermally conductive inorganic powder is a surface-modified core-shell structure nanofiller, the core-shell structure nanofiller comprises nanoparticles in the inner core (boron nitride) and an inorganic shell layer (aluminum silicate) on the surface, and the silane coupling agent is γ-glycidyloxypropyltrimethoxysilane.

[0027] A method for preparing a thermally conductive insulating silicone resin composition, such as Figure 1 As shown, the following steps are included: (1) Hydroxylation treatment: 2 g of nanoparticles were mixed with 60 mL of 40% sulfuric acid, stirred at 100 °C for 8 h, cooled, centrifuged, washed, dried, and ground to obtain hydroxylated nanoparticles; (2) Inorganic shell coating: 2 g of hydroxylated nanoparticles were added to 80 mL of ethanol, ultrasonically stirred for 30 min, 0.1 mL of silane coupling agent was dropped into it, and stirred at 70 °C for 2 h. 0.2 g of aluminum hydroxide was added, and ultrasonically stirred for 0.5 h to obtain a mixed solution. 2 mL of tetraethyl silicate was dissolved in 10 mL of ethanol, acetic acid was added dropwise to adjust the pH to 6.5, the dissolved tetraethyl silicate solution was added dropwise to the mixed solution, sodium hydroxide solution was added dropwise to adjust the pH to 9.5, stirred at 110°C for 24 h, centrifuged, washed, and dried, and the solid was heat-treated at 300°C for 3 h to obtain nanoparticles with an inorganic shell layer on the surface; (3) Preparation of suspension: Add 2 g of nanoparticles coated with an inorganic shell layer into 80 mL of ethanol, stir ultrasonically for 25 min, add 0.1 mL of silane coupling agent dropwise, and stir at 70 °C for 2 h to obtain a thermally conductive inorganic powder suspension; (4) Polymer matrix mixing: vinyl silicone oil and hydrogen silicone oil are added to the heat-conducting inorganic powder suspension, stirred and dissolved evenly, multi-walled carbon nanotubes are added, and ultrasonic dispersion treatment is performed for 30 minutes to obtain a mixed solution; (5) Degassing: Pour the mixed solution into a vacuum degasser and degas for 20 minutes to remove bubbles in the mixed solution; (6) Film preparation: The mixed solution is placed in a casting machine for casting, and dried at 60°C to completely evaporate the solvent to obtain a thermally conductive insulating silicone resin composition film with a thickness of 15 μm.

[0028] (7) Curing treatment: The film obtained by casting was placed in a curing furnace and cured at 100°C for 0.5 h. After cooling to room temperature, performance testing was performed.

[0029] Example 3 A thermally conductive insulating silicone resin composition comprises, by mass, 100 parts of vinyl silicone oil, 18 parts of hydrogenated silicone oil, 45 parts of thermally conductive inorganic powder, and 4 parts of multi-walled carbon nanotubes; the thermally conductive inorganic powder is a surface-modified core-shell structure nanofiller, the core-shell structure nanofiller comprises nanoparticles in the inner core (silicon carbide) and an inorganic shell layer (silicon dioxide) on the surface, and the silane coupling agent is γ-aminopropyltriethoxysilane.

[0030] A method for preparing a thermally conductive insulating silicone resin composition, such as Figure 1 As shown, the following steps are included: (1) Hydroxylation treatment: 1.5 g of nanoparticles were mixed with 55 mL of 35% sulfuric acid, stirred at 100 °C for 8 h, cooled, centrifuged, washed, dried, and ground to obtain hydroxylated nanoparticles; (2) Inorganic shell coating: 1.5 g of hydroxylated nanoparticles were added to 80 mL of ethanol, ultrasonically stirred for 30 min, 0.075 mL of silane coupling agent was dropped into it, and stirred at 70 °C for 2 h. 0.15 g of silicon hydroxide was added, and ultrasonically stirred for 0.5 h to obtain a mixed solution. 1.5 mL of tetraethyl silicate was dissolved in 10 mL of ethanol, acetic acid was added dropwise to adjust the pH to 6.5, the dissolved tetraethyl silicate solution was added dropwise to the mixed solution, sodium hydroxide solution was added dropwise to adjust the pH to 9.5, stirred at 110°C for 24 h, centrifuged, washed, and dried, and the solid was heat-treated at 300°C for 3 h to obtain nanoparticles with an inorganic shell layer on the surface; (3) Preparation of suspension: 1.5 g of nanoparticles coated with inorganic shells were added to 80 mL of ethanol, ultrasonically stirred for 25 min, 0.075 mL of silane coupling agent was added dropwise, and stirred at 70 °C for 2 h to obtain a thermally conductive inorganic powder suspension; (4) Polymer matrix mixing: vinyl silicone oil and hydrogen silicone oil are added to the heat-conducting inorganic powder suspension, stirred and dissolved evenly, multi-walled carbon nanotubes are added, and ultrasonic dispersion treatment is performed for 30 minutes to obtain a mixed solution; (5) Degassing: Pour the mixed solution into a vacuum degasser and degas for 18 minutes to remove bubbles in the mixed solution; (6) Film preparation: The mixed solution is placed in a casting machine for casting, and dried at 55°C to completely evaporate the solvent to obtain a thermally conductive insulating silicone resin composition film with a thickness of 15 μm.

[0031] (7) Curing treatment: The film obtained by casting was placed in a curing furnace and cured at 100°C for 0.5 h. After cooling to room temperature, performance testing was performed.

[0032] Comparative Example A conventional method for preparing a thermally conductive insulating silicone resin composition comprises the following specific steps: 470 parts by mass of aluminum oxide powder, 240 parts by mass of aluminum nitride powder and 140 parts by mass of beryllium oxide powder are mixed, and the surface is sprayed with 31 parts by mass of hexamethyldisilazane; vinyl silicone oil and dimethyl silicone oil are mixed in a mass ratio of 210:130, and added into a blender together with the surface-treated thermally conductive inorganic powder, and stirred and mixed at 110°C for 1 hour, cooled and ground to obtain a thermally conductive insulating silicone resin composition; the mixture is filled into a molding mold, and cured at 80°C for 0.5 hour to obtain a thermally conductive insulating silicone resin composition film.

[0033] Performance test: relevant performance tests were performed on the thermally conductive insulating silicone resin composition films prepared in Examples 1-3 and the comparative example; 1. Thermal conductivity: According to GB / T 3054-2008 "Determination of thermal conductivity", the film is cut into standard size (10mm×10mm×1mm) and the thermal conductivity of the sample is tested using a thermal conductivity meter.

[0034] 2. Insulation performance: According to GB / T 1410-2006 "Test method for volume resistivity and surface resistivity of solid insulating materials", place the sample between the test electrodes, use a dielectric strength tester, gradually increase the voltage to 10kV at a rate of 500 V / s, and record the breakdown voltage.

[0035] 3. Mechanical properties test: According to GB / T 1040.2-2006 "Determination of tensile properties of plastics Part 2: Test conditions for molded and extruded plastics", the film was cut into standard dumbbell-shaped specimens (width 5 mm, total length 115 mm, gauge length 50 mm), the tensile speed was 50 mm / min, and the tensile strength and elongation at break were tested using a tensile testing machine.

[0036] 4. Cyclic test: Cut the film into standard size (10mm×10mm×1mm), place it in a high temperature aging box, set the temperature to 150℃, last for 24 hours, cycle 5 times, cool to room temperature, and then perform thermal conductivity, insulation and mechanical properties tests.

[0037] The test results are shown in Table 1-2.

[0038] Table 1 Test results of relevant properties of thermally conductive insulating silicone resin composition films

[0039] Table 2 Test results of relevant properties of thermally conductive insulating silicone resin composition films

[0040] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A thermally conductive insulating silicone resin composition, characterized in that: In parts by mass, it includes 100 parts of vinyl silicone oil, 10-20 parts of hydrogenated silicone oil, 30-50 parts of thermally conductive inorganic powder, and 1-5 parts of multi-walled carbon nanotubes; wherein the thermally conductive inorganic powder is a surface-modified core-shell structure nanofiller, and the core-shell structure nanofiller includes nanoparticles in the inner core and an inorganic shell layer on the surface.

2. A thermally conductive insulating silicone resin composition according to claim 1, characterized in that: The nanoparticles are selected from one or more of aluminum oxide, boron nitride, silicon carbide, aluminum nitride, zinc oxide, titanium dioxide, and graphene, and the inorganic shell layer is aluminum silicate and / or silicon dioxide.

3. A thermally conductive insulating silicone resin composition according to claim 1, characterized in that: In the core-shell structure nanofiller, the nanoparticles account for 90-95% of the total mass of the core-shell structure nanofiller, and the inorganic shell layer accounts for 5-10% of the total mass of the core-shell structure nanofiller.

4. The thermally conductive insulating silicone resin composition according to claim 1, characterized in that: The particle size of the core-shell structure nanofiller is 100-150 nm, and the thickness of the inorganic shell layer is 5-20 nm.

5. A method for preparing the thermally conductive insulating silicone resin composition according to any one of claims 1 to 4, characterized in that: The following steps are involved: S1. Polymer matrix mixing: vinyl silicone oil and hydrogen silicone oil are added to the heat-conducting inorganic powder suspension, stirred and dissolved evenly, multi-walled carbon nanotubes are added, and ultrasonic dispersion treatment is performed for 30 minutes to obtain a mixed solution; S2. Degassing treatment: pour the mixed solution into a vacuum degasser, and perform vacuum degassing for 10-20 minutes to remove bubbles in the mixed solution, thereby obtaining a thermally conductive insulating organic silicone resin composition.

6. The method for preparing a thermally conductive insulating silicone resin composition according to claim 5, characterized in that: The preparation of the thermally conductive inorganic powder suspension comprises the following steps: (1) Hydroxylation treatment: the nanoparticles are mixed with sulfuric acid, stirred at 100°C for 8 h, centrifuged, washed, dried, and ground to obtain hydroxylated nanoparticles; (2) Inorganic shell coating: Add hydroxylated nanoparticles to ethanol, stir ultrasonically for 30 minutes, drop silane coupling agent, stir at 70°C for 2 hours, add aluminum hydroxide and / or silicon hydroxide, stir while ultrasonically for 0.5 hours to obtain a mixed solution; dissolve tetraethyl silicate in ethanol, add acetic acid to adjust the pH to 6.5, add the dissolved tetraethyl silicate solution dropwise to the mixed solution, add sodium hydroxide solution to adjust the pH to 9.5, stir at 110°C for 24 hours, centrifuge, wash, and dry, and heat treat the solid at 300°C for 3 hours to obtain nanoparticles with surface coated with an inorganic shell; (3) Preparation of suspension: Add the nanoparticles coated with an inorganic shell layer into ethanol, stir ultrasonically for 25 min, add a silane coupling agent dropwise, and stir at 70 °C for 2 h to obtain a thermally conductive inorganic powder suspension.

7. The method for preparing a thermally conductive insulating silicone resin composition according to claim 6, characterized in that: In step (1), the solid-liquid ratio of the nanoparticles to sulfuric acid is 1-3:40-70 g / mL, and the concentration of sulfuric acid is 30-50%; in step (2), the solid-liquid ratio of the hydroxylated nanoparticles to ethanol is 1-2:80 g / mL, and the solid-liquid ratio of the hydroxylated nanoparticles to the silane coupling agent is 1:0.01-0.1 g / mL; in step (3), the solid-liquid ratio of the nanoparticles coated with an inorganic shell layer to the silane coupling agent is 1:0.01-0.1 g / mL.

8. The method for preparing a thermally conductive insulating silicone resin composition according to claim 6, characterized in that: In step (2) and step (3), the silane coupling agent is γ-aminopropyltriethoxysilane or γ-glycidyloxypropyltrimethoxysilane.

9. The method for preparing a thermally conductive insulating silicone resin composition according to claim 5, characterized in that: The thermally conductive inorganic powder suspension is added in a mass ratio of 1:2-5 between the thermally conductive inorganic powder and the mixture of vinyl silicone oil and hydrogen-containing silicone oil.

10. The method for preparing a thermally conductive insulating silicone resin composition according to claim 5, characterized in that: The step S2 further includes step S3, film preparation: placing the thermally conductive insulating silicone resin composition in a casting machine for casting, drying at 40-60° C. to completely volatilize the solvent, and obtaining a thermally conductive insulating silicone resin composition film, wherein the thickness of the thermally conductive insulating silicone resin composition film is 10-20 μm.

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