DEPOSITED CALCIUM CARBONATE, METHOD OF PRODUCTION THEREOF, PAPER FILLER AND FILLED PAPER Russian patent published in 2009 - IPC C01F11/18 C09C1/02 D21H17/67 D21H21/22 

FIELD: chemistry.

SUBSTANCE: invention can be used for production of deposited calcium carbonate used as paper filler. Secondary particle diameter of deposited calcium carbonate is 1-10 mcm. Deposited calcium carbonate consists of aggregated primary particles of spindle calcium carbonate with greater particle diameter within 0.5 to 3.0 mcm, smaller diameter within 0.1 to 1.0 mcm with ration of specified diameters equal to 3 or more. Specific surface area BET of primary particles of calcium carbonate is 8-20 m²/g, cell volume is 1.5-3.5 cm³/g. Method of production of deposited calcium carbonate includes as follows. Carbon dioxide or carbon dioxide gas is injected in calcium hydroxide suspension concentrated 100-400 g/l, prepared by wet calcined liming activity of which 4 "н." HCl at third minute value is reduced to 150-400 ml. Reaction is resulted in carbonisation degree within 50 to 85%. Then 1 to 20 vol % of calcium hydroxide suspension is added. Reaction is complete with injection of carbon dioxide or carbon dioxide gas. The paper containing the specified calcium carbonate as filler is offered as well.

EFFECT: enhanced paper bulkiness.

7 cl, 2 tbl, 10 ex