Patent ID: 7682762

Claim:
A process for preparing an organic photosensitive pigment having a nanocrystal form, comprising: (a) combining together a liquid phase, a solid phase, and a solution to form a liquid-solid-solution, wherein the liquid phase comprises a fatty acid and an alcohol solvent, the solid phase comprises a sodium salt of the fatty acid, and the solution comprises metal salts; (b) mixing the liquid-solid-solution to induce a phase transfer reaction; (c) heating the reaction to generate phthalocyanine complexes with metal ions from the solid phase to form nanocrystals of the metal phthalocyanine, wherein the metal phthalocyanine nanocrystals have an average particle diameter of from about 0.5 to about 200 nm; (d) preparing the metal phthalocyanine nanocrystals for use as an organic photosensitive pigment, wherein the metal phthalocyanine nanocrystals are present in the organic photosensitive pigment in an amount of from about 10% to about 100% by weight of a total weight of the organic photosensitive pigment.