A method for preparing a
coating solution containing a cocrystallized titanyl
phthalocyanine-titanyl fluorophthalocyanine, the method comprising: dry milling a charge-generation
pigment or mixtures of charge-generation pigments; increasing the amorphousness of the
pigment mixture as determined by X-
ray crystallography using X-
radiation characteristic of Cu Kα at a
wavelength of 1.541 Å of the Bragg angle 2θ to provide an amorphous
pigment mixture; contacting the amorphous pigment mixture with a first
organic solvent having a gammac
hydrogen bonding parameter of less than 9, with or without the presence of a dispersant material, to produce a crystalline pigment of the charge-generation pigment prior to contacting the pigment with a second
organic solvent having a gammac
hydrogen bonding parameter greater than 9; mixing at least one of a second
organic solvent, a dispersant and a binder with the crystalline pigment / first
solvent mixture without isolating the crystalline pigment to produce a mixture; and, adjusting the concentrations of the first organic
solvent, crystalline pigment, binder, dispersants and second organic
solvent as required to produce the
coating solution of a selected composition.