PRODUCTION OF COATED CALCIUM CARBONATE PARTICLES

摘要

PROBLEM TO BE SOLVED: To form coating layers on the surfaces of calcium carbonate particles by an easy means at a low cost and to obtain coated calcium carbonate particles by suspending calcium carbonate particles in a precipitant-contg. aq. soln. and slowly pouring an aq. soln. of a coat forming agent into the resultant suspension. SOLUTION: Calcium carbonate particles are suspended by 0.5-20g/l in a precipitant-contg. aq. soln., preferably an aq. soln. having 0.01-10mol/l concn. of a precipitant. An aq. soln. of a coat forming agent adjusted to 0.05-0.5mol/l. concn. is poured into the resultant suspension at 0.05-1ml/min rate and coating layers are formed in 0.001-10μm thickness on the surfaces of the calcium carbonate particles. In other way, an aq. soln. of a 1st coat forming agent is slowly poured into the suspension, 1st coating layers are formed on the surfaces of the particles, an aq. soln. of a 2nd coat forming agent is then slowly poured and 2nd coating layers are formed on the 1st coating layers.