Thermally assisted transfer of small electrostatographic toner particles

Abstract

Disclosed is an improved method of making a hard copy in a process where a latent electrostatic image on an image-bearing substrate is developed by applying to the image a dry thermoplastic toner which comprises a binder polymer, and the developed image is transferred to the surface of a receiver by contacting the developed image on the substrate with the surface, then removing the surface from the substrate. The improvement comprises developing the latent electrostatic image with a toner having a particle size less than 8 micrometers, heating the surface before it contacts the developed image to a temperature such that the surface heats the toner particles when it contacts the developed image to a temperature between 10.degree. C. above the T.sub.g of the toner binder and 20.degree. C. below the T.sub.g of the toner binder, where the temperature is sufficient to fuse discrete toner particles that form the image to each other at points of contact between the particles, but insufficient to cause the contacting particles to flow into a single mass, non-electrostatically transferring the developed image to the surface, where the roughness average of the surface is less than the radius of the particles, and heating the developed image after it has been removed from the substrate to a temperature sufficient to fix it.

Dependencies are inferred from the claim text.