| abstract |
The invention relates to a method for producing aqueous active substance compositions of active substances that are hardly soluble in water, especially of active substances for use in the protection of plants and materials. The invention also relates to the active substance compositions obtained according to the inventive method and to their use in the control of harmful organisms in the protection of plants and materials. The inventive method comprises the following steps: a) providing an aqueous suspension of solid active substance particles of at least one active substance having a water solubility of not more than 5 g/l at 25 °C/1013 mbar and comprising at least one surface-active substance for stabilizing the active substance particles, whereby the active substance particles in the suspension have an average particle size, determined by dynamic light scattering, of not more than 1200 nm; b) emulsion polymerization of a first monomer composition M1 in the aqueous suspension of the active substance, whereby the monomer composition M1 comprises at least 95 % by weight, based on its total weight, of at least one neutral, monoethylenically unsaturated monomer M1.1 having a water solubility of not more than 30 g/l at 25 °C/1013 mbar, thereby obtaining an aqueous dispersion of polymer/active substance particles; and c) emulsion polymerization of a second monomer composition M2 in an aqueous dispersion of the polymer/active substance particles obtained in step b), whereby the monomer composition M2 comprises at least 60 % by weight, based on its total weight, of at least one neutral, monoethylenically unsaturated monomer M2.1 having a water solubility of not more than 30 g/l at 25 °C/1013 mbar. |