Bayer Aktiengesellschaft

Dieter Rade

Jakob Rademachers

Hans-Ulrich Hofs

Peter Woditsch

Klaus Wussow

Heinrich Heine

Manfred Mansmann

Peter Kuske

Peter Panek

Gunther Teichmann

Rolf Michael Braun

Horst Bornefeld

Dieter Messer

Wolfgang Ritter

Gerhard Trenczek

Theodor Bohmann

Spinel black pigments are prepared by annealing oxides, hydroxides or carbonates of copper, chromium and manganese and grinding the product. The manganese-yielding component is Mn.sub.3 O.sub.4.

Spinel black pigments based on copper-chromium-manganese mixed oxides, a

Novel rutile mixed phase pigment microgranulates are disclosed which comprise hemispherical particles indented to form toroid-shaped beads. The microgranulates are free-flowing, non-dust forming, and are stable in handling.

Rutile mixed phase pigment microgranulates, a process for their

Chrome green oxide useful, inter alia, as a coloring material and having a water number of 10 to 40 g/100 g is prepared by adding sulphonic acid compounds, polyphosphoric acid compounds, polyacrylic acid compounds or mixtures thereof, in quantities of from 0.1 to 2% by weight, to an aqueous suspension of chrome oxide green pigment having a BET surface area of from 1 to 20 m.sup.2 /g before drying, and then drying the suspension.

Chrome oxide green, a process for its preparation and its use

A modified hydrophobic colored or magnetic pigment or filler comprising a hydrophobic pigment or filler containing from 0.05 to 10% by weight, based on the weight of the pigment or filler, of an organopolysiloxane corresponding to the formula ##STR1## wherein x=0 to 500,

Hydrophobic pigments and fillers for incorporation in synthetic resins

A stabilized cadmium chalcogenide, in which optionally zinc and/or mercury is present in the lattice, carrying at least one coating of a sparingly-soluble sulfide is produced by adding at least one water-soluble salt of an element forming a sparingly-soluble sulfide to an aqueous chalcogenide suspension, mixing with a compound releasing sulfide ions and/or mixing the cadmium chalcogenide suspension with a soluble thio-compound of an element forming a sparingly-soluble sulfide thereby to precipitate a sparingly-soluble sulfide onto the chalcogenide, subsequently filtering, optionally washing, drying and annealing the aftertreated chalcogenide. Suitable sparingly-soluble sulfides are, for example, the sulfides of the elements Zn, Hg, In, Sn, Pb, As, Sb, Bi, V, Mo, W, Cu and Ag.

Coated stabilized cadmium chalcogenide pigments

Growing community of inventors

Krefeld, Germany

Dieter Rade