Abstract: Toner for use in the development of latent electrostatic images comprised of a resinous material and a colorant in which the resinous material is comprised of at least two polymers, the first of which has a glass transition temperature of at least 20.degree.C., and the second of which has a glass transition temperature of at least 5.degree.C. lower than the glass transition of the first. The polyblend is either a graft or block copolymer comprised of the aforesaid polymers, or a physical blend of such polymers which are incompatible with each other, prepared by dissolving the polymers in a common solvent in which the polymers are about equally soluble, followed by vigorous agitation and removal of the solvent to provide an incompatible solid mixture of the polymer.