Metallgesellschaft Aktiengesellschaft

Mitsui Minings & Melting Co., Ltd.

Mitsui Kinzoku Mitsui Maining & Smelting Co. Ltd.

Clemens Aderhold

Takao Hayashi

Nobuyoshi Kasahara

Wolf-Dieter Griebler

Norihiro Sato

Gunther Rudolph

Jorg Hocken

Manabu Hosoi

Uwe Rosin

Hans-Joachim Rohrborn

The electrically conductive, barium sulfate-containing composition consists of BaSO.sub.4 particles having a surface area of from 0.1 to 150 m.sup.2 /g. The BaSO.sub.4 particles each are provided with a SnO.sub.2 coating having a thickness of 2 to 80 nm and containing from 1 to 15% by weight of the Sb.sub.2 O.sub.3. The electrically conductive, barium sulfate-containing composition is made by a method including the steps of adding a first acidic solution containing 1 to 95% by weight SnCl.sub.4 and a basic solution to an aqueous dispersion from 50 to 800 g/l of BaSO.sub.4 to make a basic mixture having a pH from 9 to 15; then adding an acid to the basic mixture to form an acidic mixture having a pH from 4 to 1; then adding a second acid solution containing 0.5 to 60% by weight of SbCl.sub.3 to the acidic mixture; separating the electrically conductive, barium sulfate-containing composition from the acidic mixture; and drying and igniting the separated electrically conductive, barium sulfate-containing composition at 300 to 800.degree. C.

Electrically conductive barium sulfate-containing composition and

An electrically conductive powder is provided which comprises particles of zinc sulfide coated with an elecctrically conductive coating of copper sulfide wherein the zinc sulfide particles have a BET surface area of 2 to 10 m.sup.2 /g and a purity of at least 97%, and is particularly useful to impart antistatic properties to plastics, synthetic fibers, laminated papers and the like.

Electrically conductive zinc sulfide powder and process of producing the

Barium sulfate which has a chemically reactive surface is produced by a precipitation of barium ions by means of sulfate ions in an aqueous medium. In order to provide barium sulfate as a filler having functional properties, the precipitation is effected as a coprecipitation in the presence of additional anions of water-soluble compounds, which anions are coprecipitable with barium ions to form difficulty soluble barium compounds. The reactive product which contains heteroatoms is subjected to an aftertreatment which is suitable for the use that is intended in a given case.

Process for producing barium sulfate with reactive surface

Growing community of inventors

Krefeld, Germany

Clemens Aderhold