Electrophotographic copying onto sheet with fine surface indentations - giving high resolution of final image obtd. by toner transfer

摘要

Method consists of forming an electrostatic charge image on the photoconducting recording layer of an intermediate (temporary) recording sheet, colour with toner, then transferring the resultant toner image to the final recording sheet by direct contact and then, after the temporary sheet has been removed, fusing the final image on the latter sheet. The final recording sheet has a large number of small depressions distributed as a lattice over its surface. Pref. the lattice pitch of the depressions is smaller than the desired image resolution. The depressions may be conical in shape or parabolic. The small depressions concentrate the image-forming particles in a very large number of small groups or points, which reduce the coarseness of the image and lead to a high degree of resolution. It is thus possible for an electrophotographic image producing process to achieve a degree of resolution comparable with that of photographic or lithographic reproduction.