| abstract |
New iron oxide red pigments with improved color properties, the isoelectric point of the pigments being greater than 7, particularly preferably greater than 8. Process for their preparation, wherein a coating of colorless compounds of one or more elements from the group Mg, Zn, Al, La, Y, Zr, Sn, Ca is carried out on iron oxide red pigments by spraying, grinding and / or precipitation so that the content of Elements of the group Mg, Zn, La, Y, Zr, Sn, Ca 0.5 to 10 mol%, based on the total iron content of the iron oxide red pigments. |