Process for preparing precipitated calcium carbonates

Abstract

A process for the preparation of precipitated calcium carbonate by introducing CO 2 into milk of lime, in which the milk of lime is first ground, and then the CO 2 is introduced to precipitate the calcium carbonate.

What is claimed is:  
     
         1 . A process for the preparation of precipitated calcium carbonate with reproducible application-related properties, said method comprising the steps of: 
 subjecting milk of lime to specific grinding treatment to obtain ground milk of lime, and    thereafter introducing CO 2  into the ground milk of lime to precipitate the calcium carbonate.    
     
     
         2 . A process for the preparation of precipitated calcium carbonate according to  claim 1 , further comprising the steps of: 
 continuously measuring the viscosity of the milk of lime during the specific grinding treatment, and    controlling the grinding in response to the measured viscosity to regulate the quality of the ground milk of lime.    
     
     
         3 . A process for the preparation of precipitated calcium carbonate according to  claim 1 , wherein the specific grinding is controlled to produce ground milk of lime having a viscosity of at most 2500 mPas.  
     
     
         4 . A process for the preparation of precipitated calcium carbonate according to  claim 2 , wherein the specific grinding is controlled to produce ground milk of lime having a viscosity of at most 2500 mPas.