abstract |
FIELD: chemistry. n SUBSTANCE: invention can be used in chemical industry. Aqueous suspension containing calcium carbonate is preheated to a temperature of 40 to 95 °C. and wet milling is carried out. pH of the aqueous suspension is adjusted by adding the base to a pH value of ≥ 9.0. Resulting aqueous suspension is kept at a temperature of from 70 to 140 °C from 0.25 to 8 hours. Calcium carbonate-containing material has a particle-to-particle ratio d 80 average particle size, to particles of importance d 20 average particle size, [ d 80 / d 20 ], in the range from 1.5 to 4. n EFFECT: resulting material is characterized by a narrow particle size distribution, low sensitivity to moisture absorption and a low specific surface area of BET, and is used as a filler in the production of paper and paperboard, in cosmetics, in waterproofing and sealing materials, in glue materials, in paints and coatings, in fibrous materials, in plastic materials. n 24 cl, 10 tbl, 5 ex, 2 dwg |