Rheology additive based on an activated phyllosilicate for aqueous systems and mineral pre-mix mortars to generate thixotropic flow behaviour. OPTIGEL-WX improves processability and storage stability as it is highly effective at preventing solids settling. In addition, it reduces the sagging tendency after application which makes it possible to achieve greater layer thicknesses. OPTIGEL-WX is inorganic and stable to diluted acids and bases. OPTIGEL-WX is suitable for a variety of aqueous systems for pH neutral, acidic and basic coatings. It is recommended for use in architectural, wood and furniture coatings.