Abstract: Provided is a dielectric imaging sheet useful in electrographic imaging, wherein a particulate solid incorporated into the dielectric coating has been treated with an acyloxy or amino terminated polysiloxane. Short-chain polysiloxanes, e.g., 3 to 8 siloxane units, are preferred as the treating agent, with the amino group being preferably lower alkyl substituted and the acyloxy group being preferably lower acyloxy. Use of the specially treated particulate solid reduces moisture induced imaging defects upon using the dielectric sheet in electrographic imaging.

Abstract: An improved vesicular matrix prepared by employing regulated inner incompatibility to produce enhanced nucleation. The inner incompatibility is produced by copolymerizing a first monomer with a small amount of a second monomer wherein a homopolymer of the second monomer would be incompatible with a polymer of the first monomer, or by blending a first polymer or copolymer with a small amount of a highly incompatible second polymer or copolymer.