CUBIC MAGNESIUM OXIDE POWDER AND METHOD FOR PRODUCING THE SAME

摘要

Disclosed is a magnesium oxide powder having a cubic shape and a large average particle diameter. Also disclosed is a method for producing such a magnesium oxide powder. Specifically disclosed is a magnesium oxide powder whose particles have a cubic shape when observed with a scanning electron microscope. This magnesium oxide powder has a 50% cumulative particle diameter (D<SUB>50</SUB>), as determined by a laser diffraction/scattering particle size distribution measuring method, of not less than 1.0 µm. This powder can be obtained by firing a magnesium oxide precursor in the presence of 0.5-30% by mass of a halide ion relative to the total mass of the precursor in a closed system.