Process for preparing a particle-containing composition from tetrahydro-3,5-dimethyl-1,3,5-thiadiazine-2-thione

摘要

In the present invention, there is described a process for preparing a product from tetrahydro-3,5-dimethyl-1,3,5-thiadiazine-2-thione having such distribution of particles that less than 7 percent by weight of these particles have smaller diameters than 100 microns, more than 50 percent by weight of these particles have smaller diameters than 200 microns and more than 90 percent by weight of these particles have smaller diameters than 300 microns and more than 95 percent by weight of these particles have smaller diameters than 400 microns wherein the preparation process is characterized mixing a first aqueous solution containing methyl ammonium-(N-methyldithiocarbamate) with a second aqueous solution containing formaldehyde followed by subsequent separation and drying of the resulting solid substance wherein the ratio of the concentrations of the dithiocarbamate functional groups and formaldehyde is constant in the reaction mixture during the reaction or in the range of +- 20 percent of the stoichiometrically required amount of the used reactant, and the solid substance is then separated from the resulting suspension.