Abstract: The present invention relates to very durable bismuth-based inorganic pigments with a light vivid yellow to orange color corresponding to the following general formula: BiV(1−n)XnO(4−3n) in which X is a halogen or a mixture of halogens and n can vary from 0 to 1. The invention also relates to the process for the manufacture of such pigments.

Abstract: The present invention relates to a pigment based on bismuth vanadate with a bright vivid yellow to orange color exhibiting improved resistance, in particular an improved resistance to heat, characterized in that it is coated with several layers of inorganic compounds in several successive stages, the last layer being based on a zinc and boron compound. The present invention also relates to the process for producing this pigment and to its application.

Abstract: A process for preparing a pigment based on bismuth vanadate by reacting an acidic solution of bismuth nitrate with a basic solution of ammonium metavanadate to form a precipitate in a very acidic reaction mixture with a pH value of between 1 and 2. The pH of the reaction mixture is brought to a value of about 7, and the temperature of the reaction mixture is established at 80.degree. C. or higher for a period of about 30 minutes. The reaction mixture is stirred for a period of time of at least one half hour until a pH of approximately 6.5 is reached, and then the precipitate is filtered from the reaction mixture. Finally, the precipitate is washed and dried to obtain a dried pigment.