The present invention relates to a method for producing a metal nitride by igniting a raw material powder containing a metal powder filled in a reaction vessel under a nitrogen atmosphere and propagating nitriding combustion heat generated by a nitriding reaction of the metal to the whole raw material powder, the method including forming a heat insulating layer made of a material having nitrogen permeability and inert to the nitriding reaction on an upper surface of a layer made of the raw material powder. According to the present invention, it is possible to provide a method for reducing the amount of unreacted metal powder when producing a metal nitride by a combustion synthesis method.

One aspect of the present disclosure provides a hexagonal boron nitride powder having a purity of 98 mass % or more and a specific surface area of less than 2.0 m.sup.2/g.

One aspect of the present disclosure provides a hexagonal boron nitride powder having a purity of 98 mass % or more and a specific surface area of less than 2.0 m.sup.2/g.

A fabrication method of a hexagonal boron nitride (h-BN)-based thermally-conductive composite film includes the following steps: S1. attaching an adhesive layer to an h-BN film carried on a carrier film, and separating the h-BN film from the carrier film to obtain a film in which an adhesive layer side is defined as a side A and an h-BN film side is defined as a side B; S2. attaching an adhesive layer to the side B of the film obtained in S1; S3. pasting a high-power graphite film to the side B of a film obtained in S2; S4. attaching an adhesive layer to the side B of a film obtained in S3; and S5. shaping a film obtained in S4 according to a required size. The present fabrication method is conducive to improving the production efficiency or yield rate of a thermally-conductive film product and the product quality.

A process for producing a material in the form of nanosheets by ball milling of crystals of the material, wherein the ball milling takes place in the presence of a reactive gas.

One aspect of the present invention provides a boron nitride powder that contains aggregated particles formed through aggregation of primary particles of boron nitride. The cumulative pore volume of the boron nitride powder within a fine pore radius of 0.02-1.2 μm as measured by a mercury porosimeter is 0.65 mL/g or less.

One aspect of the present invention provides a boron nitride powder that contains aggregated particles formed through aggregation of primary particles of boron nitride. The cumulative pore volume of the boron nitride powder within a fine pore radius of 0.02-1.2 μm as measured by a mercury porosimeter is 0.65 mL/g or less.

Provided is a method for effectively modifying a surface of a h-BN particle including a (0001) plane, which is a base surface of h-BN, with a variety of materials.

A method for producing a surface-coated hexagonal boron nitride particle of one embodiment includes mixing a hexagonal boron nitride particle (a), a coupling agent (b), and a catalyst (c) having a polar group and an aromatic ring in a solvent to form a layer containing a condensate of the coupling agent on at least a portion of a surface of the hexagonal boron nitride particle.

A method and apparatus for preparing boron nitride nanotubes (BNNTs) according to an embodiment may ensure mass-production, may increase yield by reducing a production time, and may prepare BNNTs with high purity.

A method and apparatus for preparing boron nitride nanotubes (BNNTs) according to an embodiment may ensure mass-production, may increase yield by reducing a production time, and may prepare BNNTs with high purity.