PROCESS OF ENHANCED PREPARATION OF BISMUTH-VANADATE COMPOUNDS

摘要

Improved process for preparing bismuth vanadate pigments and solid solutions based on bismuth vanadate by a) mixing a solution of a bismuth(III) salt containing if necessary one or more further metal salts or a mixture thereof with the aqueous solution of a vanadate salt containing if necessary a molybdate, tungstenate or sulphate salt or a mixture thereof, and b) subsequently aftertreating the resulting suspension to convert the initially amorphously precipitated particles into crystalline compounds, characterised in that fluoride ions are used during mixing and/or in the course of the subsequent aftertreatment stage. The pigments thus produced are notable in application in particular for high colour strength and hiding power.