PROCESS FOR PREPARATION OF PHOTOCONDUCTIVE IMAGING MEMBERS
Original Publication Date: 1976-Jul-31
Included in the Prior Art Database: 2004-Mar-27
Xerox Disclosure Journal
There is described a process for the preparation of an anisotropic solid phase dispersion of photoconductive particles in a polymeric matrix. According to the process photoconductive particles, which may be organic, inorganic or mixtures thereof and which are preferably less than about 2 microns in average diameter, are physically dispersed in a crystalline thermoplastic polymeric matrix which typically has a soften point in excess of about 70°C, is fluid at temperatures below about 100°Cand has an intrinsic viscosity of less than about 105 poise. The dispersion is confined between two planar electrodes, heated to a temperature in excess of the softening point of the thermoplastic material and subjected to an electrical field established between the electrodes until at least some of the photoconductive particles migrate and align themselves along the lines of force of the field, Subse~~ quently the thermoplastic material is allowed to solidify thus immobilizing the photoconductive particles within the polymer in their aligned condition. During the immobili~ zation procedure, an electrical field is maintained across the dispersion at a level sufficient to prevent random diffusion of photoconductive particles into regions of the polymer which had formerly been depleted of these particles. In a preferred embodiment, the dispersion is subjected to blanket exposure with activating electro~ magnetic radiation during the alignment of the photocon~ ductive particles.