Iron oxide red pigments, process for the production of iron oxide red pigments and use thereof

摘要

Iron oxide red pigments (I) have a lightness L asterisk = 36.0-44.0 and values of a asterisk = 24-30 and b asterisk = 14-26 in the pure tone; and L asterisk = 59-66, a asterisk = 18-30 and b asterisk = 4-26 in a lightened tone, all in CIELAB units; and contain 0.012-0.12 wt.% manganese (Mn), 0.05-0.59 wt.% chloride (Cl), both with respect to the pigment, and less than 40 mg chromium (Cr)/kg pigment. Independent claims are also included for the preparation of pigments (I) from iron oxide yellow pigments (II) or iron oxide black pigments (III).