ABSTRACT
The ubiquitous presence of electro-photographic office machines in the modern workplace and home may lead one to believe that it has been this way for many decades. It bears remembering that this was not always so. Electro-photography is the term used to describe document printing or copying via toner and a photo-conductive imaging drum. Although paper types and the specific materials and configuration of components within the devices have changed over the years, the basic steps of the process are the same. The interaction of materials with electrostatics is the key to how and why such document production is possible. Early devices did not produce high resolution copies by the standards of today. Such early devices were also not able to reproduce larger areas of solid black or dark color due to the manner of toner deposition. Advances in instrumentation and interdisciplinary research have provided some additional techniques that may assist in examinations.
