The invention relates to a method for production of concentrates of water-soluble active agents, wherein, in a waterless method using solid active agents as starting materials, the crystals of an active agent are uniformly distributed in a first organic solvent to which a dispersing agent is added, the viscosity of the solution thus obtained is adjusted as applicable by a suitable auxiliary agent, a polymer creator is added to the solution thus obtained, in a second organic solvent as applicable, wherein the viscosity of either the solution to be added or the solution to be obtained is adjusted by the addition of a suitable auxiliary agent, and a crosslinking agent having at least two functional groups in a third organic solvent is given to the obtained solution, wherein the viscosity of either the added or obtained solution is in turn adjusted by the addition of a suitable auxiliary agent and the polymer creator is selected from the group comprising low-viscosity polymethylene-polyphenylisocyanate, preferably having an average NCO content of 25-35, particularly preferably 30-32%, and mixtures thereof.