Boron nitride and process for preparing the same

摘要

The present invention provides a polycrystalline hexagonal boron nitride compound comprising fine crystals of the order of nanometers.The present invention also provides a hexagonal boron nitride characterized in that the boron nitride is 20 to 200 nm in mean particle size and comprises at least 80 wt. % of particles having sizes in the range of the mean particle size ±30%.The present invention further provides a fine hexagonal boron nitride powder characterized in that the powder comprises particles in the form of circular disks or elliptical disks having a minor axis La, a major axis Lb and a thickness t which satisfy the following expressions