The invention relates to synthetic material dispersions consisting of (a) an aqueous phase of solutions of hydrophilic melamine resin precondensates and a latent hardening catalyst in water or in mixtures of water and alcohols C1-C6, (b) an organic nanophase in the form of nanometric droplets and/or nanoparticles derived from 70-99 % of the melamine resin precondensates which are insoluble in water and etherifieds and contain hardening acid catalysts and acid impermiability agents, (c) dispersion agents at a concentration of 1-10 mass % in relation to the total mass of the melamine resin precondensates. The ratio between the hydrophilic melamine resin precondensates and the water and etherifieds-insoluble melamine resin precondensates ranges from 10:1 to 1:10, the water content in the inventive synthetic material dispersions ranging from 8 and 50 mass %. Said synthetic material dispersions are used for producing flat coated products which are externally used in the form of laminates, of coated flat carrying materials or moulded coated bodies for construction or for sports and recreation.