Abstract: Provided is a production method of a carbon sheet having a structure intertwining only carbon nanotubes and having a porosity of 5% to 90%. The method comprises: removing a solvent from a dispersion liquid containing carbon nanotubes, spacer particles, and the solvent to obtain a primary sheet containing the carbon nanotubes and the spacer particles; and removing the spacer particles from the primary sheet. Alternatively, the method comprises: impregnating a porous substrate made from carbon with a dispersion liquid containing carbon nanotubes and a solvent, to obtain a dispersion liquid-impregnated porous substrate; and removing the solvent from the dispersion liquid-impregnated porous substrate. Alternatively, the method comprises: dispersing carbon nanotubes in a solvent to obtain a dispersion liquid, wherein an average bundle diameter of the carbon nanotubes in the dispersion liquid is 0.5 ?m or more and 1,000 ?m or less; and removing the solvent from the dispersion liquid.

Abstract: A carbon film excellent in electromagnetic shielding performance is provided. The carbon film is made of a carbon nanotube assembly and has a fractal dimension of 2.6 or more and 4 or less in a wavenumber range of 0.0001 (1/?) or more and 0.001 (1/?) or less when a scattering profile obtained by performing ultra-small-angle X-ray scattering on at least one surface of the carbon film is fitted to the Beaucage equation, while having a porosity of 80% or more and 95% or less.

Abstract: A carbon film is formed from carbon nanotube assemblies. In the carbon film, a pore distribution curve indicating the relationship between the pore size and the Log differential pore capacity obtained based on mercury intrusion porosimetry has at least one peak with a log differential pore capacity of 1.0 cm3/g or more within a pore size range of 10 nm or more and 100 ?m or less.

Abstract: Disclosed is an electromagnetic wave absorbing sheet which includes a sheet-shaped fibrous substrate and carbon nanotubes positioned in a space inside in a thickness direction of the sheet-shaped fibrous substrate, wherein the fibrous substrate is composed of organic fibers, the carbon nanotubes comprise single-walled carbon nanotubes as a main component, and the electromagnetic wave absorbing sheet has an electrical conductivity of 0.7 S/cm or more and 20 S/cm or less.

Abstract: Provided is a production method of a carbon sheet having a structure intertwining only carbon nanotubes and having a porosity of 5% to 90%. The method comprises: removing a solvent from a dispersion liquid containing carbon nanotubes, spacer particles, and the solvent to obtain a primary sheet containing the carbon nanotubes and the spacer particles; and removing the spacer particles from the primary sheet. Alternatively, the method comprises: impregnating a porous substrate made from carbon with a dispersion liquid containing carbon nanotubes and a solvent, to obtain a dispersion liquid-impregnated porous substrate; and removing the solvent from the dispersion liquid-impregnated porous substrate. Alternatively, the method comprises: dispersing carbon nanotubes in a solvent to obtain a dispersion liquid, wherein an average bundle diameter of the carbon nanotubes in the dispersion liquid is 0.5 ?m or more and 1,000 ?m or less; and removing the solvent from the dispersion liquid.

Abstract: The present disclosure is directed to providing a carbon film having an excellent shield performance against electromagnetic waves. The carbon film of the present disclosure is a carbon film made of a carbon nanotube assembly, wherein a pore distribution curve of the carbon film indicating the relationship between the pore size and the Log differential pore capacity obtained from an adsorption isotherm at 77 K of liquid nitrogen based on the Barrett-Joyner-Halenda method has a peak in which the Log differential pore capacity is maximized within a pore size range of 10 nm or more and 100 nm or less, and the value of the Log differential pore capacity at the peak is 1.2 cm3/g or more.

Abstract: A carbon nanotube assembly satisfies at least one of the following conditions (1) to (3): (1) an FT-IR spectrum of a CNT dispersion obtained by dispersing the CNT assembly has a peak based on plasmon resonance of the CNTs in a wave number range of greater than 300 cm?1 and 2000 cm?1 or less; (2) the highest peak in a differential pore capacity distribution of the CNT assembly is located within a pore size range of more than 100 nm and less than 400 nm; and (3) a two-dimensional spatial frequency spectrum of an electronic micrographic image of the CNT assembly has at least one peak within a range of 1 ?m?1 or more and 100 ?m?1 or less.

Abstract: Provided is a material that has excellent handleability and processability, and that when used as a support for a different material, enables support of the different material up to an inner part thereof. A carbon sheet contains one or more carbon nanotubes and has a porosity of not less than 48% and not more than 90%. The carbon sheet preferably includes: a porous substrate made from carbon; and the carbon nanotubes, attached to the porous substrate. The carbon nanotubes contained in the carbon sheet are preferably single-walled carbon nanotubes. Moreover, the carbon nanotubes contained in the carbon sheet preferably have a nitrogen adsorption specific surface area of 600 m2/g or more.

Abstract: Provided is a material that has excellent handleability and processability, and that when used as a support for a different material, enables support of the different material up to an inner part thereof. A carbon sheet contains one or more carbon nanotubes and has a porosity of not less than 5% and not more than 90%. The carbon sheet preferably includes: a porous substrate made from carbon; and the carbon nanotubes, attached to the porous substrate. The carbon nanotubes contained in the carbon sheet are preferably single-walled carbon nanotubes. Moreover, the carbon nanotubes contained in the carbon sheet preferably have a nitrogen adsorption specific surface area of 600 m2/g or more.

Abstract: An electromagnetic wave absorbing sheet includes a sheet-shaped fibrous substrate and a plurality of carbon nanotubes attached to the sheet-shaped fibrous substrate. The attached amount of the carbon nanotubes in the electromagnetic wave absorbing sheet is 5 mass % or more. The electromagnetic wave absorbing sheet has a surface resistance of 20 ?/sq. or more.

Abstract: Disclosed is an electromagnetic wave absorbing sheet which comprises a sheet-shaped fibrous substrate and carbon nanotubes positioned in a space inside in a thickness direction of the sheet-shaped fibrous substrate, wherein the fibrous substrate is composed of organic fibers, the carbon nanotubes comprise single-walled carbon nanotubes as a main component, and the electromagnetic wave absorbing sheet has an electrical conductivity of 0.7 S/cm or more and 20 S/cm or less.

Abstract: Provided is a material that has excellent handleability and processability, and that when used as a support for a different material, enables support of the different material up to an inner part thereof. A carbon sheet contains one or more carbon nanotubes and has a porosity of not less than 5% and not more than 90%. The carbon sheet preferably includes: a porous substrate made from carbon; and the carbon nanotubes, attached to the porous substrate. The carbon nanotubes contained in the carbon sheet are preferably single-walled carbon nanotubes. Moreover, the carbon nanotubes contained in the carbon sheet preferably have a nitrogen adsorption specific surface area of 600 m2/g or more.

Abstract: Provided are a carbon film having excellent electrical conductivity and a method of producing this carbon film. The carbon film has a film surface glossiness at 60° of at least 2 and not more than 500. The method of producing the carbon film includes forming a carbon film by removing a solvent from a fibrous carbon nanostructure dispersion liquid containing the solvent and one or more fibrous carbon nanostructures.

Abstract: Disclosed is a sheet which comprises a fibrous substrate and carbon nanotubes attached to fibers constituting the fibrous substrate. The carbon nanotubes in the sheet comprise single-walled carbon nanotubes as a main component.

Abstract: Provided is a carbon film including: a plurality of fibrous carbon nanostructures; and a conductive carbon, wherein the plurality of fibrous carbon nanostructures has a BET specific surface area of 500 m2/g or more. Also provided is a method of producing a carbon film, the method including mixing a conductive carbon into a fibrous carbon nanostructure dispersion liquid containing a plurality of fibrous carbon nanostructures having a BET specific surface area of 500 m2/g or more, a dispersant, and a solvent, and subsequently removing the solvent to form a carbon film.

Abstract: A carbon nanotube film includes an assembly of a plurality of carbon nanotubes, wherein the plurality of carbon nanotubes includes one or more carbon nanotubes having at least partially collapsed structures. A method for producing a carbon nanotube film includes forming a carbon nanotube film by removing a solvent from a carbon nanotube dispersion liquid containing the solvent, a dispersant, and a plurality of carbon nanotubes including one or more carbon nanotubes having at least partially collapsed structures.

Abstract: Provided are a carbon film having excellent electrical conductivity and a method of producing this carbon film. The carbon film has a film surface glossiness at 60° of at least 2 and not more than 500. The method of producing the carbon film includes forming a carbon film by removing a solvent from a fibrous carbon nanostructure dispersion liquid containing the solvent and one or more fibrous carbon nanostructures.

Abstract: Provided is a carbon film including: a plurality of fibrous carbon nanostructures; and a conductive carbon, wherein the plurality of fibrous carbon nanostructures has a BET specific surface area of 500 m2/g or more. Also provided is a method of producing a carbon film, the method including mixing a conductive carbon into a fibrous carbon nanostructure dispersion liquid containing a plurality of fibrous carbon nanostructures having a BET specific surface area of 500 m2/g or more, a dispersant, and a solvent, and subsequently removing the solvent to form a carbon film.

Abstract: A carbon nanotube film includes an assembly of a plurality of carbon nanotubes, wherein the plurality of carbon nanotubes includes one or more carbon nanotubes having at least partially collapsed structures. A method for producing a carbon nanotube film includes forming a carbon nanotube film by removing a solvent from a carbon nanotube dispersion liquid containing the solvent, a dispersant, and a plurality of carbon nanotubes including one or more carbon nanotubes having at least partially collapsed structures.