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CN-122010101-A - Carbon material, preparation method thereof, display screen and electronic equipment

CN122010101ACN 122010101 ACN122010101 ACN 122010101ACN-122010101-A

Abstract

The embodiment of the application provides a carbon material, a preparation method thereof, a display screen and electronic equipment, wherein the carbon material comprises a plurality of stacked carbon atom layers, the in-plane thermal diffusion coefficient of the carbon material is more than or equal to 800mm 2 /s, the Young modulus of the carbon material is 1000Mpa-6000Mpa, the surface roughness Ra of the carbon material is less than or equal to 800nm, and the elongation at break of the carbon material is more than or equal to 2%. The carbon material has the advantages of ultrahigh thermal diffusivity, high modulus, low surface roughness and higher elongation at break, and can be used in appearance devices such as flexible display modules and the like, so that the device has high heat conduction performance and good flexibility and appearance fineness.

Inventors

  • XIAO GUIYU
  • ZHONG LEI
  • CHEN QIU
  • JIN LINFANG
  • ZHOU XIAO

Assignees

  • 华为技术有限公司

Dates

Publication Date
20260512
Application Date
20250427

Claims (20)

  1. 1. The carbon material is characterized by comprising a plurality of stacked carbon atom layers, wherein the in-plane thermal diffusivity of the carbon material is more than or equal to 800mm 2 /s, the Young modulus of the carbon material is 1000Mpa-6000Mpa, the surface roughness Ra of the carbon material is less than or equal to 800nm, and the elongation at break of the carbon material is more than or equal to 2%.
  2. 2. The carbon material of claim 1, wherein the crystalline grains of the carbon material have a crystallographic L c size greater than or equal to 50nm.
  3. 3. The carbon material of claim 1 or 2, wherein the carbon material has a graphitization degree of 0.97 or greater.
  4. 4. A carbon material according to any one of claims 1-3, wherein the interlayer distance of the carbon atom layers of the multi-layered stack is 0.3nm-0.5nm.
  5. 5. The carbon material as defined in any one of claims 1 to 4, wherein the carbon material has a primary film property in a thickness range of 2mm or less.
  6. 6. The carbon material of any one of claims 1-5, wherein the carbon material is bendable.
  7. 7. The carbon material of any one of claims 1-6, wherein the carbon material comprises a carbon film, sheet, or plate.
  8. 8. A method for producing a carbon material, comprising: Mixing graphene oxide dispersion liquid with an additive to obtain mixed slurry, coating the mixed slurry on a substrate, and drying to form a graphene oxide film and then peeling the graphene oxide film from the substrate; Carrying out heat treatment on the graphene oxide film under the condition of isolating air, so that graphene oxide is subjected to pyrolysis reaction to generate graphene, and a film material after heat treatment is obtained, wherein the heat treatment comprises heating to 250-400 ℃ at a first heating rate for a first time, then heating to 1000-1200 ℃ for a second time, and then heating to 2900-3300 ℃ at a second heating rate for a third time; and carrying out calendaring treatment on the film material subjected to the heat treatment to obtain the carbon material with the required thickness.
  9. 9. The method of claim 8, wherein the transition metal compound comprises one or more of a transition metal oxide, a transition metal carbide, and a transition metal halide.
  10. 10. The method according to claim 8 or 9, wherein the transition metal compound comprises one or more of Fe 2 O 3 、Fe 5 C 2 、FeCl 3 、Fe 2 (SO 4 ) 3 、TiC、TiCl 4 、NiO、Ni(NO 3 ) 2 、NiSO 4 、NiCl 2 、CoCl 2 、CoO, the boron-containing material comprises boron simple substance and/or boron-containing compound, the boron-containing compound comprises one or more of boric acid, triphenylboron, trimethyl borate and neopentyl glycol biborate, the nitrogen-containing material comprises one or more of urea, ammonia water, trimethylamine, nitromethane and melamine, and the phosphorus-containing material comprises one or more of trimetaphosphate and tetrametaphosphoric acid.
  11. 11. The preparation method according to any one of claims 8 to 10, wherein the graphene oxide dispersion and the additive are mixed according to a mass ratio of graphene oxide to additive of 99.95:0.05 to 90:10.
  12. 12. The method according to any one of claims 8 to 11, wherein the first temperature rising rate is 5 ℃ to 20 ℃ per minute, the first time is 10 hours to 60 hours, the second time is 20 hours to 80 hours, the second temperature rising rate is 0.2 ℃ to 5 ℃ per minute, and the third time is 15 hours to 200 hours.
  13. 13. The production method according to any one of claims 8 to 12, wherein the heat treatment is performed with a pressurizing treatment during heating to 1000 ℃ to 1200 ℃ at a pressurizing pressure of 0.1Mpa to 10Mpa.
  14. 14. The method according to any one of claims 8 to 13, wherein a heat-conducting medium is used to clamp the graphene oxide films during the heat treatment, so that each graphene oxide film is sandwiched between two heat-conducting mediums, and the heat-conducting coefficient of the heat-conducting mediums is greater than or equal to 100W/m x K.
  15. 15. The method of any one of claims 8-14, wherein the substrate comprises an organic polymer film or a metal foil, and the drying temperature is 25 ℃ to 150 ℃.
  16. 16. The method according to any one of claims 8 to 15, wherein the calendering treatment uses a pressure of 0.1Mpa to 120Mpa.
  17. 17. A thermally conductive composite material, characterized in that the thermally conductive composite material comprises at least one carbon material and at least two additional layers which are arranged in a stacked manner, each carbon material is arranged between the two additional layers, each additional layer is independently selected from a metal layer, a polymer layer or a carbon fiber reinforced resin layer, and the carbon material comprises the carbon material according to any one of claims 1 to 7 or the carbon material prepared by the preparation method according to any one of claims 8 to 16.
  18. 18. The thermally conductive composite of claim 17, wherein the metal layer is selected from a copper layer, a nickel layer, a stainless steel layer, or a magnesium aluminum alloy layer.
  19. 19. The thermally conductive composite of claim 17 or 18, wherein the polymer layer comprises a flexible polymeric material comprising one or more of polyethylene terephthalate, polytetrafluoroethylene, polyimide, thermoplastic polyurethane elastomer, polyamide, parylene, optical cement.
  20. 20. The thermally conductive composite of claim 19, wherein the flexible polymeric material has a compression ratio of 0-20%.

Description

Carbon material, preparation method thereof, display screen and electronic equipment Technical Field The embodiment of the application relates to the technical field of heat conduction materials, in particular to a carbon material, a preparation method thereof, a display screen and electronic equipment. Background At present, the power consumption of 5G and AI electronic products is increased sharply, the heat productivity is increased sharply, the electronic products are extremely light and thin, and the heat dissipation of high-power consumption scenes under ultra-thin thickness is required to meet the higher requirements on the performance of heat dissipation devices. The heat conducting carbon material is used as a heat radiating device in the electronic product to transfer heat in the heat concentration area to the low-temperature area, and the scheme for reducing the temperature of the hot area and realizing efficient and flexible heat radiation is commonly used in the industry. However, the existing heat-conducting carbon material is difficult to have high heat dissipation effect and good flexibility and appearance refinement in the appearance devices such as the flexible display screen, and the problems of particles, film marks, orange peel marks, bending peeling and the like of the flexible display screen are easily caused, as shown in fig. 1, fig. 1 is a photograph of the display screen adopting the existing heat-conducting carbon material, and as can be seen from fig. 1, the display screen has the problems of refinement of particles, film marks, orange peel marks and the like. Disclosure of Invention In view of this, the embodiment of the application provides a carbon material, a preparation method thereof, a display screen and electronic equipment, wherein the carbon material has an ultrahigh thermal diffusion coefficient, a high modulus, a low surface roughness and a high elongation at break, and can be used in appearance devices such as a flexible display module and the like, so that the device has high heat conduction performance, and simultaneously has good flexibility and appearance refinement. In a first aspect, an embodiment of the present application provides a carbon material, where the carbon material includes a plurality of stacked carbon atom layers, an in-plane thermal diffusion coefficient of the carbon material is equal to or greater than 800mm 2/s, a young modulus of the carbon material is 1000Mpa-6000Mpa, a surface roughness Ra of the carbon material is equal to or less than 800nm, and an elongation at break of the carbon material is equal to or greater than 2%. The carbon material 100 provided by the embodiment of the application has the advantages of ultrahigh thermal diffusivity, high modulus, low surface roughness and higher elongation at break, and small thickness, and can be used in appearance devices such as flexible display modules, so that the device has light weight, high heat conductivity, good flexibility and appearance fineness, and therefore, the problems of heat dissipation and appearance fineness of the display modules can be solved at the same time, and the foldable requirement can be met. In an embodiment of the present application, the crystal grain of the carbon material has a crystallographic L c size of 50nm or more. The crystal grain L c of the carbon material is larger in size, and is beneficial to obtaining the carbon material with the original film characteristic in a larger thickness range, so that the carbon material can be directly used in a scene with high heat dissipation and soaking requirements, the carbon material with the required thickness is prevented from being bonded by adopting a plurality of layers of glue, and the heat dissipation requirements of high-power consumption equipment are better met. In an embodiment of the present application, the graphitization degree of the carbon material is greater than or equal to 0.97. The graphitization degree is an index for measuring the degree to which carbon atoms form a close-packed hexagonal graphite crystal structure, and the closer the lattice size is to the ideal graphite, the higher the graphitization degree of the lattice constant is. In an embodiment of the present application, the interlayer distance of the carbon atom layers of the multi-layered stack is 0.3nm to 0.5nm. The smaller carbon layer spacing is beneficial to improving the in-plane thermal diffusion performance of the carbon material. In the embodiment of the application, the carbon material has the characteristics of a primary film within the thickness range of less than or equal to 2 mm. Namely, the carbon materials within the thickness range of 2mm are not required to be bonded by adopting glue, so that the thermal diffusivity and the structural stability of the carbon materials can be improved. In an embodiment of the present application, the carbon material is bendable. The carbon material has the characteristic of being be