Lithopone

Uses

Lithopone is mainly used in coating materials with relatively high pigment concentrations. Examples are primers, plastic masses, putties and fillers, artists’ colors, and emulsion paints. An important property of lithopone is its low binder requirement, giving paint products with good flow and application properties. It is suitable for almost all binder media, and has good wetting and dispersing properties. With optimum feed composition, good dispersion can be achieved simply by the action of a dissolver. It can be economically advantageous to use lithopone in combination with TiO2 pigments; the good hiding power of the TiO2 pigments is combined with the economic and technical advantages of lithopone. Due to the strong shift of the absorption band towards the blue, lithopone is especially useful as a white pigment for UV-cured paint systems. Zinc compounds have fungicidal and algicidal effects, and inclusion of lithopone or Sachtolith in paint formulations for exterior use therefore helps prevent the growth of algae or fungi.
The material advantages of lithopone are used in plastics (e.g., good lightfastness and clear bluish-white shade). The product also imparts very good extruding properties to the plastic resulting in high throughput rates and economic extruder operation. In fire-resistant systems, ca. 50% of the flame retardant antimony trioxide can be replaced by nontoxic lithopone without any adverse effect.