VERFAHREN ZUR HERSTELLUNG VON TIO(PFEIL ABWAERTS)2(PFEIL ABWAERTS)-KOMPOSITIONSPIGMENTEN

摘要

In a process for producing a composite TiO2 pigment which contains a white inert extender, the neutralization is simplified and the need for washing processes is eliminated in that a metatitanic acid suspension, which contains free and combined sulfuric acid and has been purified for the removal of chromophoric elements, is neutralized by an addition of calcium oxide and/or barium oxide in quantities which are stoichiometric with respect to total sulfate, the calcium sulfate and/or barium sulfate is precipitated in an intimate mixture with the metatitanic acid, and the coprecipitate is separated and dried. The precipitated calcium sulfate and/or barium sulfate is contained in the coprecipitate in an amount from 1 to 25% by weight.