A method for preparing a nanodispersion comprising the steps of: (i) introducing into a milling apparatus a solid fluorinated phthalocycanine pigment according to Formula (I): ##STR00001## Wherein M is a metal cation chosen from Groups 1b, 2b, 2a or 3a of the Periodic Table of the Elements; R is fluorine, a perfluoroalkyl or a perfluoroaryl group; z is 1 to 4; L is an anionic ligand; and n is 0 or 1 such that the overall charge on the molecular unit is neutral; followed by milling with agitation the solid fluorinated phthalocyanine in an organic solvent into a suspension of particles so that at least 80 volume % of the particles have a particle size of less than 100 nm.