“Chemical” or “polymerisation” toner technologies offer the ability to manufacture small particle size (e.g. 5μm) toners by economically viable processes. ZENECA has developed a process in which polymer latices, pigments and, if desired, waxes and charge control agents, can be aggregated in a controlled manner to produce toners with a mean size from below 5 to above 10 μm. Narrow particle size distributions are attained across the size range without classification. The process allows the particle shape to be controlled from highly irregular through to spherical. The process has been used to make black and coloured toners.