The invention concerns a method for producing ultrafine suspensions,characterized in that a substance in the form of a solid product at 20 ~C isdissolved in a solvent, in that the solvent is very rapidly substantiallydrawn from said solution, in that the powder thus obtained, whereof theparticles have an average particle-size distribution of the order of 1 to 50µm (by laser diffractometry) is dispersed in a dispersing medium, and inthat the resulting suspension is treated subsequently, using average to highforces, so as to obtain a suspension whereof the solid matter particles have aaverage particle-size distribution (by photon correlation spectroscopy) lessthan 3 µm, preferably less than 1µm (1000 nm), and in particular lessthan 400 nm, more particularly still, less than 200 nm.
