| abstract |
Ink cartridges containing ink compositions containing nanometer scale pigment particles are produced by preparing a pigment solution including a solubilized pigment-Lewis acid complex and an aprotic solvent system, separating the pigment from the pigment solution to form pigmented particles either by precipitating pigment nanoparticles or by dyeing colloidal particles with the solubilized pigment-Lewis acid complex, concentrating the pigmented particles, then dispersing the pigmented particles in a formulating solvent to form an ink composition, and finally introducing the ink composition into an ink cartridge. The ink compositions are particularly suitable for use in ink jet ink cartridges. |