Aqueous dispersions, dry powders and double dispersions containing difficultly water-soluble or insoluble organic UV filter substances (e.g. triazines) for use in plastics, lacquers, cosmetics or pharmaceuticals

摘要

Aqueous dispersions of difficultly water-soluble or water-insoluble organic UV filter substances (I) contain at least one such substance as a colloidally-dispersed phase in amorphous or partly amorphous form. Independent claims are also included for: (1) the production of the dispersions by (a) treating a molecularly-disperse organic solvent solution of (I) with an aqueous solution of a protective colloid so as to convert the hydrophobic phase of the substance into a colloid disperse phase and then removing the organic solvent or (b) treating a molecularly-disperse organic solvent solution containing (I) and also a water-insoluble polymer with water or with an aqueous solution of a protective colloid so as to convert the hydrophobic phase of (I) and the polymer into a colloid disperse phase and then removing the organic solvent; and (2) production of dry powders by removal of the water and drying optionally in the presence of a coating material, these powders then being optionally converted into double dispersions by emulsifying in an oil.