Fine flaky boehmite particles amd process for the preparation of the same

摘要

Fine flaky boehmite particles which have an orthorhombic crystal form and a specified crystal face grown in the form of a flat plate, and a process for the preparation of fine flaky boehmite particles which comprises subjecting aluminum hydroxide or hydrated alumina having a particle size adjusted to the order of submicrons to hydrothermal treatment in water or an aqueous alkali solution at a temperature of 150. degree. C. or above under a pressure of 100 atm or below. The fine flaky boehmite particles are useful as a starting material for the preparation of fine flaky alumina particles or as a filler suitable for a pigment for coating materials, a filler for rubbers and plastics and a coating material for paper making.