Bayer Aktiengesellschaft

Willi Hennings

Franz Hund

Horst Brunn

Peter Kresse

Wolfgang Rambold

Henning Erfurth

Wilhelm Holznagel

Friedrich Kindervater

A zinc ferrite pigment comprising, by weight, about 99.8 to 90% of ZnFe.sub.2 O.sub.4 and about 0.2 to 10% of the component system (1-x)Al.sub.2 O.sub.3 and xP.sub.2 O.sub.5 wherein 0&lt;x&lt;1 is produced by calcining a suitable mixture of compounds. The resulting pigments are of high color quality and are substantially halogen-free, rendering them especially useful industrially even as anti-corrosion pigments.

Halogen-free zinc ferrite yellow pigments containing alumina and

A temperature-stable inorganic yellow pigment of the composition Fe.sub.2 TiO.sub.5 .multidot. x TiO.sub.2, where x is from 0 to about 15, with a particle diameter of less than about 1 micron is produced by forming an aqueous suspension of at least one finely divided iron compound selected from the group consisting of iron oxide, iron oxide hydroxide, iron hydroxide and iron carbonate and at least one finely divided titanium compound selected from the group consisting of titanium dioxide and titanium dioxide oxide hydrate, the iron and titanium compounds being present in accordance with the stoichiometric composition Fe.sub.2 TiO.sub.5 .multidot. x TiO.sub.2 where x is from 0 to about 15, removing the aqueous phase from the mixed suspension, and calcining the residue at a temperature from about 600.degree. C to 1100.degree. C.

Temperature-stable inorganic yellow pigments

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Krefeld, Germany

Willi Hennings