The method of electrophotographically manufacturing a luminescent screen assembly on a substrate for use within a CRT, according to the present invention, includes the steps of: forming a conductive layer on the substrate; overcoating the conductive layer with a photoconductive solution comprising an organic polymeric material, a suitable photoconductive dye, a plasticizer and a solvent to form a photoconductive layer; and, then, establishing an electrostatic charge on the photoconductive layer. Selected areas of the photoconductive layer are exposed to visible light to affect the charge thereon, and the photoconductive layer is developed with charged screen structure material. The improved method utilizes a dialkyl phthalate plasticizer which is selected from the group consisting of dibutylphthalate (DBP), dioctylphthalate (DOP), and diundecylphthalate (DUP).