WO2024048396A1 - Feuille de graphite et sa méthode de production - Google Patents

Feuille de graphite et sa méthode de production Download PDF

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WO2024048396A1
WO2024048396A1 PCT/JP2023/030358 JP2023030358W WO2024048396A1 WO 2024048396 A1 WO2024048396 A1 WO 2024048396A1 JP 2023030358 W JP2023030358 W JP 2023030358W WO 2024048396 A1 WO2024048396 A1 WO 2024048396A1
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graphite
graphite sheet
particles
thickness direction
sheet according
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PCT/JP2023/030358
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English (en)
Japanese (ja)
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文武 糸瀬
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パナソニックＩｐマネジメント株式会社
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    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B32/00—Carbon; Compounds thereof
    • C01B32/20—Graphite
    • C01B32/205—Preparation
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L23/00—Details of semiconductor or other solid state devices
    • H01L23/34—Arrangements for cooling, heating, ventilating or temperature compensation ; Temperature sensing arrangements
    • H01L23/36—Selection of materials, or shaping, to facilitate cooling or heating, e.g. heatsinks
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
    • H01L23/00—Details of semiconductor or other solid state devices
    • H01L23/34—Arrangements for cooling, heating, ventilating or temperature compensation ; Temperature sensing arrangements
    • H01L23/36—Selection of materials, or shaping, to facilitate cooling or heating, e.g. heatsinks
    • H01L23/373—Cooling facilitated by selection of materials for the device or materials for thermal expansion adaptation, e.g. carbon

Definitions

  • the present disclosure relates to a graphite sheet and a method for manufacturing a graphite sheet, and specifically relates to a graphite sheet having a plurality of graphite layers and a method for manufacturing the graphite sheet.
  • Patent Document 1 discloses a thermally conductive sheet using a graphite sheet obtained by thermally decomposing an organic film, in which a region other than the end surface of the graphite sheet has a surface direction that is aligned with each graphene layer constituting the graphite sheet.
  • a thermally conductive sheet is disclosed that is configured to be substantially perpendicular to the c-axis of the graphite layer, and a surface perpendicular to the c-axis of the graphene layer is exposed at the end surface of the graphite sheet.
  • the thermal conductivity in the plane direction of the graphite sheet is low due to the fact that the graphite layers are mostly arranged in the plane direction. While the thermal conductivity in the thickness direction is very high at about 2000 W/mK, the thermal conductivity in the thickness direction is low at about 5 W/mK, and the thermal resistance in the thickness direction is large.
  • An object of the present disclosure is to provide a graphite sheet and a method for manufacturing a graphite sheet that can reduce thermal resistance in the thickness direction.
  • a graphite sheet according to one embodiment of the present disclosure has a plurality of graphite layers.
  • a method for producing graphite according to one aspect of the present disclosure includes a first step, a second step, and a third step.
  • a solution or suspension containing graphene oxide and a surfactant is prepared.
  • a precursor film is formed using the solution or suspension.
  • the precursor film is heat-treated to obtain a graphite sheet having a plurality of graphite layers.
  • FIG. 1 is an electron micrograph of a cross section of the graphite sheet of Example 1.
  • FIG. 2 is an electron micrograph of a cross section of the graphite sheet of Example 6.
  • a graphite sheet can be placed between a heating element and a heat radiating element and tightened with a screw, etc., thereby compressing the graphite sheet and bringing it into close contact with the heating element and the heat radiating element, thereby transferring the heat generated by the heating element to the heat radiating element.
  • the graphite layer formed is mostly arranged in the plane direction, so the thermal resistance in the plane direction is very small.
  • the thermal resistance in the thickness direction which is the heat conduction direction, was large.
  • the inventors have repeatedly studied how to reduce the thermal resistance in the thickness direction by controlling the arrangement of the multiple graphite layers formed during the production of graphite sheets.
  • the present disclosure was completed based on the discovery that the thermal resistance in the thickness direction can be reduced by using a surfactant or by using a surfactant and graphite particles during manufacturing.
  • the graphite sheet of the first embodiment of the present disclosure has multiple graphite layers.
  • the graphite sheet of the second embodiment of the present disclosure further includes a plurality of graphite particles between and at least partially within the graphite layers.
  • the graphite sheet according to the present disclosure thermal resistance in the thickness direction can be reduced.
  • the reason why the graphite sheet according to the present disclosure achieves the above effects by having the above structure is not necessarily clear, it can be inferred as follows, for example.
  • the graphite layer formed is arranged not only in the in-plane direction, but also in a proportion of the graphite arranged in a direction that has a component perpendicular to the in-plane direction. It is thought that there will be more layers.
  • the arrangement of the graphite layer formed changes due to the interaction between the surfactant and a raw material such as graphene oxide.
  • the surfactant is thermally decomposed during the heat treatment to form the graphite sheet, and a portion of the thermally decomposed surfactant, such as a residue, contributes to bonding the graphite layers together.
  • the number of places where the graphite layers are bonded to each other increases in the thickness direction, so it is thought that the thermal resistance in the thickness direction becomes smaller.
  • the proportion of graphite layers arranged in a direction other than the plane direction increases.
  • the graphite layer is arranged in a direction having a thickness direction component in the vicinity of the graphite particles. As a result, the thermal resistance in the thickness direction of the graphite sheet can be reduced.
  • the method for manufacturing a graphite sheet according to the first embodiment of the present disclosure includes a first step, a second step, and a third step.
  • a solution or suspension containing graphene oxide and a surfactant is prepared.
  • a precursor film is formed using the solution or suspension.
  • the precursor film is heat treated to obtain a graphite sheet having a plurality of graphite layers.
  • the solution or suspension in the first step of the graphite sheet manufacturing method of the first embodiment further includes a plurality of graphite particles.
  • a graphite sheet with low thermal resistance in the thickness direction can be obtained by a simple method.
  • the graphite sheet of the first embodiment (hereinafter also referred to as graphite sheet (X)) has a plurality of graphite layers (hereinafter also referred to as graphite layer (A)). That is, the graphite sheet (X) is formed by laminating a plurality of graphite layers (A) in the thickness direction.
  • the “graphite layer” is a layer made of graphite (graphite) that constitutes a single cleavage plane.
  • the graphite layer usually includes one or more layers of graphene (a layer in which carbon atoms are arranged in a hexagonal honeycomb lattice, and is usually a single layer).
  • the average thickness of the graphite layer (A) is, for example, 0.001 ⁇ m or more and 20 ⁇ m or less, and preferably 0.01 ⁇ m or more and 10 ⁇ m or less.
  • the graphite layer (A) is preferably formed from graphene oxide, and more preferably formed from graphene oxide in the presence of a surfactant.
  • the graphite layer (A) is formed from graphene oxide mainly having a single-layer structure, and is also formed in the presence of a surfactant that can interact with the oxygen-containing groups of graphene oxide. Therefore, it is thought that the proportion of graphite sheets (X) arranged in the thickness direction increases, and as a result, the graphite sheet (X) can have a smaller thermal resistance in the thickness direction.
  • the graphite sheet (X) of the second embodiment includes a plurality of graphite layers (A) and a plurality of graphite particles (hereinafter also referred to as graphite particles (B)).
  • the plurality of graphite particles (B) are present between the graphite layers (A) and at least partially within the layers. That is, the graphite sheet (X) has a plurality of graphite particles (B) between and at least partially within the plurality of graphite layers (A) stacked in the thickness direction.
  • the graphite sheet (X) increases the proportion of graphite layers (A) arranged in a direction having a thickness direction component.
  • graphite layer The plurality of graphite layers (A) are the same as the plurality of graphite layers (A) in the first embodiment.
  • Graphite particles mean graphite particles. "Graphite” is one of the allotropes of carbon, and is also called graphite. However, the graphite particles (B) are different from the graphite layer (A).
  • graphite examples include natural graphite such as graphite stone and graphite minerals, artificial graphite (synthetic graphite) such as highly oriented pyrolytic graphite, and scaly graphite.
  • the graphite particles (B) preferably include particles of artificial graphite. In this case, the thermal resistance in the thickness direction of the graphite sheet (X) can be further reduced.
  • Examples of the shape of the graphite particles (B) include flat shapes such as scales, scales, and flakes, and spherical shapes. It is preferable that the graphite particles (B) have at least one of a spherical shape and a scaly shape. In this case, the thermal resistance in the thickness direction of the graphite sheet (X) can be further reduced.
  • the average particle diameter of the plurality of graphite particles (B) is preferably 0.1 ⁇ m or more and 100 ⁇ m or less. By setting the average particle size of the graphite particles (B) within the above range, the thermal resistance can be further reduced.
  • the average particle diameter of the graphite particles (B) is more preferably 1 ⁇ m or more and 60 ⁇ m or less, even more preferably 3 ⁇ m or more and 40 ⁇ m or less, and particularly preferably 10 ⁇ m or more and 30 ⁇ m or less.
  • the average particle diameter of graphite particles refers to the volume-based 50% cumulative distribution diameter (D50) of a plurality of (for example, 100) graphite particles.
  • the average particle size of the plurality of graphite particles (B) is preferably larger than the average thickness of the graphite layer (A).
  • the average particle size of the plurality of graphite particles (B) is preferably larger than the average thickness of the graphite layer (A).
  • the graphite layer (A) and at least a portion of the plurality of graphite particles (B) are bonded.
  • the graphite particles (B) are not discharged even when cut, and the thermal resistance in the thickness direction of the graphite sheet (X) can be further reduced.
  • bonds include covalent bonds between carbon atoms of the graphite layer (A) and carbon atoms of the plurality of graphite particles (B). It is thought that such a covalent bond is likely to be formed, for example, during the formation of the graphite sheet (X) due to the action of a part of the thermally decomposed surfactant such as a residue generated by heat treatment.
  • the distance between the plurality of graphite layers (A) is preferably smaller than the average particle diameter of the plurality of graphite particles (B). Further, the distance between the plurality of graphite layers (A) is preferably 25 ⁇ m or less. In such a case, the graphite layer (A) is arranged so as to avoid the graphite particles (B), and as a result, the graphite layer (A) is likely to be arranged in the thickness direction of the graphite sheet (X).
  • the average thickness of the graphite sheet (X) is, for example, 1 ⁇ m or more and 150 ⁇ m or less, preferably 10 ⁇ m or more and 120 ⁇ m or less, and more preferably 20 ⁇ m or more and 100 ⁇ m or less.
  • a portion of the graphite layer (A) extends in the plane direction of the graphite sheet (X), and in the vicinity of the plurality of graphite particles (B), at least a portion of the graphite layer (A) extends in the plane direction of the graphite sheet (X). Preferably, it extends in the thickness direction.
  • the proportion of the formed graphite layer (A) in the direction having a thickness direction component is higher in the vicinity thereof. It is thought that it will become larger. In this way, by having the graphite layer (A) that has a component in the thickness direction and is oriented diagonally, the thermal resistance in the thickness direction of the graphite sheet (X) can be efficiently reduced. Can be done.
  • the compression rate of the graphite sheet (X) when compressed at 200 kPa in the thickness direction is preferably 55% or more. By increasing the compressibility of the graphite sheet (X), the thermal resistance in the thickness direction can be further reduced.
  • the compression rate is more preferably 60% or more, and even more preferably 65% or more.
  • the compression ratio is, for example, 75% or less. Note that the compression ratio is the value of (T0-T1)/T0 expressed as a percentage, where T0 is the initial thickness and T1 is the thickness when the pressure is released after applying a pressure of 200 kPa.
  • the thermal resistance in the thickness direction of the graphite sheet (X) when the graphite sheet (X) is compressed in the thickness direction at 200 kPa is preferably 0.4 Kcm 2 /W or less. In this case, the thermal resistance in the thickness direction of the graphite sheet (X) can be made sufficiently small.
  • the thermal resistance in the thickness direction of the graphite sheet (X) is more preferably at most 0.27 Kcm 2 /W, even more preferably at most 0.24 Kcm 2 /W, and even more preferably at most 0.19 Kcm 2 /W. It is particularly preferable that there be.
  • the method for manufacturing the graphite sheet (X) of the first embodiment includes a first step, a second step, and a third step, as shown below. Each step will be explained below.
  • Graphene oxide is graphene (which mainly includes compounds with a structure in which carbon atoms are arranged in a hexagonal honeycomb lattice) modified with oxygen-containing groups such as carboxyl groups, carbonyl groups, and hydroxyl groups. It is.
  • a surfactant is a substance that acts on the interface of a substance to change its properties, and usually has a structure that includes both a hydrophilic part and a hydrophobic part within the molecule.
  • the surfactant examples include anionic surfactants, ionic surfactants such as cationic surfactants, and nonionic surfactants.
  • the surfactant preferably includes an ionic surfactant, and more preferably an anionic surfactant.
  • anionic surfactants include sulfonic acids or salts thereof, carboxylic acids or salts thereof, and the like.
  • sulfonic acid salts and carboxylic acid salts include alkali metal salts such as lithium salts, sodium salts, and potassium salts; alkaline earth metal salts such as magnesium salts, calcium salts, and barium salts; Examples include amine salts such as triethanolamine salts.
  • alkali metal salts are preferred, at least one of sodium salts and potassium salts is more preferred, and sodium salts are even more preferred.
  • sulfonic acid examples include aliphatic sulfonic acid and aromatic sulfonic acid.
  • aliphatic sulfonic acids examples include octane sulfonic acid and dodecyl sulfonic acid.
  • salts of aliphatic sulfonic acids include sodium octanesulfonate and sodium dodecylsulfonate.
  • aromatic sulfonic acid examples include aromatic sulfonic acids having an alkyl group such as dodecylbenzenesulfonic acid, and aromatic sulfonic acids not having an alkyl group such as naphthalenetrisulfonic acid.
  • salts of aromatic sulfonic acids include salts of aromatic sulfonic acids having an alkyl group such as sodium dodecylbenzenesulfonate, salts of aromatic sulfonic acids having no alkyl group such as trisodium naphthalene trisulfonate, etc. Can be mentioned.
  • carboxylic acid examples include tetradecanoic acid (myristic acid), hexadecanoic acid (palmitic acid), octadecanoic acid (stearic acid), and the like.
  • carboxylic acid salts include sodium myristate, sodium palmitate, and sodium stearate.
  • the anionic surfactant preferably contains at least one of aliphatic sulfonic acids and salts thereof, and aromatic sulfonic acids and salts thereof, and at least one of aliphatic sulfonic acids and salts thereof. It is more preferable to include one or the other. In this case, the thermal resistance in the thickness direction of the obtained graphite sheet (X) can be more effectively reduced.
  • the aromatic sulfonic acid and its salts preferably include aromatic sulfonic acids and salts thereof having an alkyl group, and more preferably include salts of aromatic sulfonic acids having an alkyl group.
  • the surfactant since the surfactant has an alkyl group bonded to an aromatic ring, it is possible to more effectively reduce the thermal resistance in the thickness direction of the obtained graphite sheet (X).
  • alkyl group examples include linear alkyl groups such as n-octyl group, n-dodecyl group, n-tetradecyl group, n-hexadecyl group, n-octadecyl group, n-icosyl group, isooctyl group, isododecyl group, etc.
  • Examples include branched alkyl groups.
  • the alkyl group is preferably a linear alkyl group, more preferably an n-dodecyl group.
  • the length of the carbon chain of the alkyl group is preferably 9 or more and 17 or less. When the length of the carbon chain is 9 or more, the thermal resistance of the graphite sheet (X) can be further reduced. When the length of the carbon chain is 17 or less, the graphene oxide dispersion can be made more stable.
  • the length of the carbon chain of the alkyl group is more preferably 10 or more and 14 or less, most preferably 12. "Length of carbon chain of alkyl group" refers to the number of carbon atoms in the longest carbon chain in the alkyl group.
  • the solution or suspension in the first step may be prepared by, for example, adding an aqueous solution of graphene oxide to an aqueous solution of a surfactant, and stirring the resulting mixture using, for example, a stirring defoaming machine. Can be done.
  • a precursor film is formed using the solution or suspension prepared in the first step.
  • the precursor film in the second step is produced by, for example, applying the solution or suspension obtained in the first step onto a base material such as PET to a predetermined thickness using a device such as a coater, and then drying it. It can be formed by, for example.
  • the coating thickness is, for example, 0.1 mm or more and 3 mm or less.
  • the drying temperature is, for example, 30°C or higher and 80°C or lower.
  • the precursor film formed in the second step is heat-treated to obtain a graphite sheet (X) having a plurality of graphite layers (A).
  • the heat treatment in the third step can be performed, for example, by firing the precursor film formed in the second step. This firing is usually performed by applying a load to the precursor film.
  • the temperature of this firing is, for example, 2000°C or more and 3000°C or less, preferably 2500°C or more and 2800°C or less.
  • the graphite sheet manufacturing method of the second embodiment differs from the graphite sheet manufacturing method of the first embodiment described above in that, in the first step, a plurality of graphite particles (B) are added in addition to graphene oxide and a surfactant. They differ in that they further contain solutions or suspensions, but are otherwise similar.
  • a solution or suspension containing graphene oxide, a surfactant, and a plurality of graphite particles (B) is prepared.
  • the graphene oxide and surfactant are the same as those used in the graphite sheet manufacturing method of the first embodiment.
  • the plurality of graphite particles (B) have at least one of a spherical shape and a scaly shape.
  • the plurality of graphite particles (B) include particles of artificial graphite.
  • the average particle diameter of the plurality of graphite particles (B) is preferably 10 ⁇ m or more and 100 ⁇ m or less. It is thought that by setting the average particle size of the graphite particles (B) within the above range, in the graphite sheet (X), the proportion of the graphite layer (A) arranged in a direction having a thickness direction component increases. As a result, the thermal resistance in the thickness direction of the graphite sheet (X) can be further reduced.
  • the average particle diameter of the graphite particles (B) is more preferably 15 ⁇ m or more and 60 ⁇ m or less, and even more preferably 18 ⁇ m or more and 40 ⁇ m or less.
  • the weight ratio of the plurality of graphite particles (B) is preferably 1% or more and 70% or less with respect to the solid content of graphene oxide and the total amount of the plurality of graphite particles. In this case, a strong graphite sheet (X) with low compression ratio can be obtained.
  • the weight ratio is more preferably 10% or more and 60% or less, and even more preferably 25% or more and 45% or less.
  • the graphite sheet (X) obtained in the third step preferably has a plurality of graphite particles (B) between the graphite layers (A) and at least partially within the layers.
  • a graphite sheet was manufactured by the following procedure. [First step] (Preparation of solution or suspension) (raw materials) The raw materials used for preparing the solution or suspension are shown below.
  • ⁇ Graphene oxide graphene oxide aqueous dispersion (solid content concentration 1.8% by weight)
  • ⁇ Graphite particles MAG-4 (average particle size 3.9 ⁇ m), SGS20 (average particle size 20 ⁇ m), G3 (average particle size 38 ⁇ m) manufactured by Fuji Graphite Industries Co., Ltd.
  • SDBS Sodium dodecylbenzenesulfonate
  • SDS Sodium dodecylsulfonate
  • SO Sodium octanesulfonate
  • TNTS Trisodium naphthalene trisulfonate
  • Example 1 0.45 g of artificial graphite powder with an average particle size of 20 ⁇ m was placed in a small bottle, and 12 g of an aqueous solution (1.5% by weight) of sodium dodecylbenzenesulfonate (SDBS) was added thereto and stirred. Next, 45 g of graphene oxide aqueous dispersion (1.8% by weight) was added to this and stirred with a stirring defoamer to prepare a solution or suspension. (Examples 2 to 5) Example 1 except that graphite particle powder having the average particle diameter shown in Table 1 below was used in an amount to give the weight % shown in Table 1, and a surfactant of the type and weight % shown in Table 1 was used.
  • SDBS sodium dodecylbenzenesulfonate
  • a solution or suspension was prepared in the same manner as above.
  • Example 6 A solution or suspension was prepared in the same manner as in Example 1, except that graphite particles were not blended.
  • Examples 7 to 9 A solution or suspension was prepared in the same manner as in Example 6, except that the types and weight percentages of surfactants shown in Table 1 were used.
  • Comparative example 1 45 g of graphene oxide aqueous dispersion (1.8% by weight) was placed in a small bottle and stirred with a stirring defoamer to prepare a solution or suspension.
  • FIG. 1 An electron micrograph of a cross section of the graphite sheet of Example 1 is shown in FIG. 1, and an electron micrograph of a cross section of the graphite sheet of Example 6 is shown in FIG.
  • the proportion of graphite layers arranged in a direction having a thickness direction component is high.
  • FIG. 1 it can be seen that the tendency for alignment in this direction is high in the vicinity of graphite particles.
  • Thermal conductivity in the thickness direction From the measured thermal resistance in the thickness direction and the measured value of the average thickness after compression, the thermal conductivity in the thickness direction was calculated using the following formula (2).
  • Thermal conductivity in the thickness direction (W/mK) Average thickness after compression ( ⁇ m)/(Thermal resistance in thickness direction (W/) x 100) ...(2)
  • [Material thermal conductivity] The relationship between the pressing force in the thickness direction and the thermal resistance in the thickness direction was measured.
  • the pressing force was set at six points: 50 kPa, 100 kPa, 200 kPa, 300 kPa, 500 kPa, and 600 kPa, and the thermal resistance in the thickness direction was measured for each case.
  • the measured values of thermal resistance for each pressing force were plotted, the slope thereof was determined, and the reciprocal of this slope was taken as the material thermal conductivity.
  • the graphite sheet (X) according to the first aspect of the present disclosure has a plurality of graphite layers (A).
  • the thermal resistance in the thickness direction of the graphite sheet (X) can be reduced.
  • a plurality of graphite particles (B) are further included between the graphite layers (A) and at least partially within the layers.
  • the graphite particles are contained while maintaining the structure of the graphite layer (A), thereby increasing the proportion of the graphite layer (A) arranged in a direction having a thickness direction component. It is considered possible to reduce the thermal resistance in the thickness direction of the graphite sheet (X).
  • At least a portion of the graphite layer (A) and at least a portion of the plurality of graphite particles (B) are combined.
  • the graphite particles (B) are not discharged even when cut, and the thermal resistance in the thickness direction of the graphite sheet (X) can be further reduced.
  • the average particle size of the plurality of graphite particles (B) is larger than the average thickness of the graphite layer (A).
  • the graphite layer (B) having an average particle diameter larger than the average thickness of the graphite layer (A)
  • the proportion of A) can be increased, and as a result, the thermal resistance in the thickness direction of the graphite sheet (X) can be made smaller.
  • a part of the graphite layer (A) extends in the plane direction of the graphite sheet (X), and a plurality of graphite particles ( In the vicinity of B), at least a portion of the graphite layer (A) extends in the thickness direction of the graphite sheet (X).
  • the graphite layer (A) has a component in the thickness direction of the graphite sheet (X) in the vicinity of the graphite particles (B) and is oriented obliquely, so that the graphite The thermal resistance in the thickness direction of the sheet (X) can be efficiently reduced.
  • the compression rate of the graphite sheet (X) when compressed at 200 kPa in the thickness direction is 55% or more. It is.
  • the thermal resistance in the thickness direction of the graphite sheet (X) can be further reduced.
  • thermal resistance in the thickness direction of the graphite sheet (X) when the graphite sheet (X) is compressed at 200 kPa in the thickness direction is 0.1 Kcm 2 /W or more and 0.4 Kcm 2 /W or less.
  • the thermal resistance in the thickness direction of the graphite sheet (X) can be made sufficiently small.
  • the graphite layer (A) is formed from graphene oxide.
  • the graphite layer (A) from graphene oxide, it is possible to further reduce the thermal resistance in the thickness direction of the graphite sheet (X).
  • the method for manufacturing a graphite sheet (X) according to the ninth aspect of the present disclosure includes a first step, a second step, and a third step.
  • a solution or suspension containing graphene oxide and a surfactant is prepared.
  • a precursor film is formed using the solution or suspension.
  • the precursor film is heat-treated to obtain a graphite sheet (X) having a plurality of graphite layers (A).
  • a graphite sheet (X) with low thermal resistance in the thickness direction can be obtained by a simple method.
  • the solution or suspension in the first step further contains a plurality of graphite particles (B).
  • the thermal resistance in the thickness direction of the obtained graphite sheet (X) can be further reduced.
  • a plurality of graphite particles (B) are added between and at least in part of the graphite layer (A).
  • the content of the graphite particles (B) in the obtained graphite sheet (X) increases the proportion of the graphite layer (A) arranged in the direction having the thickness direction component. It is thought that it is possible to increase the thermal resistance in the thickness direction of the graphite sheet (X).
  • the plurality of graphite particles (B) are at least one of spherical and scaly.
  • the thermal resistance in the thickness direction of the graphite sheet (X) obtained can be further reduced.
  • the plurality of graphite particles (B) include particles of artificial graphite.
  • the thermal resistance in the thickness direction of the obtained graphite sheet (X) can be made smaller.
  • the average particle size of the plurality of graphite particles (B) is 10 ⁇ m or more and 100 ⁇ m or less.
  • the fourteenth aspect by using graphite particles (B) having an average particle size within the above range, the proportion of the graphite layer (A) arranged in a direction having a thickness direction component is increased. As a result, the thermal resistance of the graphite sheet (X) obtained can be further reduced.
  • the surfactant includes an anionic surfactant.
  • the thermal resistance in the thickness direction of the obtained graphite sheet (X) can be more effectively reduced.
  • the anionic surfactant contains at least one of an aliphatic sulfonic acid and a salt thereof, and an aromatic sulfonic acid and a salt thereof.
  • the thermal resistance of the obtained graphite sheet (X) can be more effectively reduced.
  • the aromatic sulfonic acid and its salt include an aromatic sulfonic acid and its salt having an alkyl group.
  • the thermal resistance of the obtained graphite sheet (X) can be more effectively improved. Can be made smaller.
  • the solid content of graphene oxide and the total amount of the plurality of graphite particles (B) in the solution or suspension in the first step, is 1% or more and 70% or less.
  • the eighteenth aspect by setting the ratio of graphite particles (B) to the total of graphene oxide and graphite particles (B) within the above range, it is possible to obtain a strong graphite sheet (X) with a low compressibility. can.

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Abstract

La présente invention aborde le problème de la fourniture d'une feuille de graphite dont la résistance thermique dans la direction de l'épaisseur peut être abaissée. La feuille de graphite a une pluralité de couches de graphite.
PCT/JP2023/030358 2022-08-31 2023-08-23 Feuille de graphite et sa méthode de production WO2024048396A1 (fr)

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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2005019132A1 (fr) * 2003-08-26 2005-03-03 Matsushita Electric Industrial Co., Ltd. Element de conductivite thermique elevee, son procede de production et systeme de dissipation thermique mettant en oeuvre un tel element
WO2015045641A1 (fr) * 2013-09-26 2015-04-02 株式会社カネカ Feuille de graphite, procédé pour la fabriquer, carte stratifiée pour câblage, matériau de câblage en graphite, et procédé pour fabriquer une carte de câblage
US20190075683A1 (en) * 2016-09-13 2019-03-07 Huawei Technologies Co., Ltd. Heat sink, preparation method therefor, and communications device
JP2019206447A (ja) * 2016-09-30 2019-12-05 コニカミノルタ株式会社 グラファイト成形体の製造方法
JP2022511459A (ja) * 2018-11-30 2022-01-31 ピーアイ・アドバンスド・マテリアルズ・カンパニー・リミテッド 配向性に優れたポリイミドフィルムから製造されるグラファイトシートおよびその製造方法

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2005019132A1 (fr) * 2003-08-26 2005-03-03 Matsushita Electric Industrial Co., Ltd. Element de conductivite thermique elevee, son procede de production et systeme de dissipation thermique mettant en oeuvre un tel element
WO2015045641A1 (fr) * 2013-09-26 2015-04-02 株式会社カネカ Feuille de graphite, procédé pour la fabriquer, carte stratifiée pour câblage, matériau de câblage en graphite, et procédé pour fabriquer une carte de câblage
US20190075683A1 (en) * 2016-09-13 2019-03-07 Huawei Technologies Co., Ltd. Heat sink, preparation method therefor, and communications device
JP2019206447A (ja) * 2016-09-30 2019-12-05 コニカミノルタ株式会社 グラファイト成形体の製造方法
JP2022511459A (ja) * 2018-11-30 2022-01-31 ピーアイ・アドバンスド・マテリアルズ・カンパニー・リミテッド 配向性に優れたポリイミドフィルムから製造されるグラファイトシートおよびその製造方法

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