Ube Material Industries, Ltd.

Naoto Nishida

Koji Nakamura

Seiji Yamaguchi

Akira Yoshida

Tatsuki Okutsu

Naoki Funabashi

Takashi Arase

Satoshi Shimmatsu

Coated magnesium oxide particles having high filling efficiency and high mass-productivity and suitable for a thermal conductive filler are provided, the coated magnesium oxide particles being coated magnesium oxide particles in which the surface of magnesium oxide particles is coated with at least one of a fatty acid and a fatty acid metal salt, and wherein X in relation to particles is defined as X=[a BET specific surface area diameter calculated from a BET specific surface area of the particles]&#xf7;[Dof the particles], provided that Dis a particle diameter at 50% accumulation in a cumulative particle size distribution of the particles, the magnesium oxide particles having X of less than 0.2 and Dof 5 to 100 &#x3bc;m, and the coated magnesium oxide particles having X of 0.2 or more, Dof 5 to 100 &#x3bc;m, and oil absorption of less than 25 mL/100 g.

Coated magnesium oxide particles and method of producing the same, and thermal conductive resin composition

A magnesium oxide powder has: a median diameter (D) of 5 to 100 &#x3bc;m; a MgO purity of 98% by mass or more; a Ca compound content of 2% by mass or less in terms of CaO; and when the magnesium oxide powder is immersed in pure water and allowed to stand at 95&#xb0; C. for 24 hours, a mass ratio of calcium ions to magnesium ions, Ca/Mg, in an aqueous solution of 10 or less.

Magnesium oxide powder, production method therefor, thermally-conductive resin composition, thermally-conductive grease, and thermally-conductive coating material

To provide magnesium oxide which is excellent in hydration resistance and hardly causes volume expansion due to hydration and the like, a resin composition containing the same, and a method for producing the magnesium oxide powder. Magnesium oxide powder having a coating layer mainly comprising basic magnesium carbonate in the surface layer, when the amounts of substances of water vapor and carbon dioxide among the gas generated by thermal decomposition at 50 to 500&#xb0; C. are respectively designated as m-HO and m-CO, in a heating evolved gas analysis (EGA-MS) method, the molar fraction represented by m-CO/(m-HO+m-CO) being within the range of 0.3 to 0.6.

Magnesium oxide powder, resin composition including same, and method for producing magnesium oxide powder

A thermally conductive resin filler including a sintered body containing at least magnesium oxide, calcium oxide, and silicon oxide, the thermally conductive filler being characterized in that, when the molar number of calcium element contained in the total composition of the sintered body in terms of calcium oxide (CaO) is defined as MCa, and the molar number of silicon element contained in the total composition of the sintered body in terms of silicon oxide (SiO) is defined as MSi, the molar ratio of the calcium oxide (CaO) to the silicon oxide (SiO) represented by MCa/MSi is in the range of 0.1 or more and less than 2.0.

Growing community of inventors

Ube, Japan

Naoto Nishida