PRODUCTION OF SPHERICAL HEMATITE PARTICLE WITH EVEN DIAMETER

PURPOSE: To obtain in an industrially advantageous way fine spherical hematite particles easy to control the size thereof, excellent in dispersibility, by adding a ferrous salt, etc., and urea to a ferric salt followed by mixing to effect dissolution in water and then by heating the resultant solution. CONSTITUTION: (A) A ferric salt having a concentration of pref. 0.03-0.3mol/L when dissolved is incorporated with about 0.01 molar times of (B) (i) a ferrous salt 1×10- to 1×10- in concentration or (ii) iron powder 0.01-0.1g/L in iron salt concentration followed by addition, as precipitant, of (C) at least 10 molar times of urea pref. 0.3-4mol/L in concentration, and the resultant system is mixed in water into an aqueous solution, which is, in turn, heated to 70 deg.C or higher, thus obtaining the objective spherical hematite particles 0.01-1.0μm in diameter. The particles can be used as a colorant for coating materials, ink, synthetic resins, construction materials and the ceramic industry, and is also useful for fluophors, ultraviolet absorbers and magnetic materials, etc.