Abstract: A development electrode arrangement located in closely-spaced parallel relation to the charge retaining surface of a moving electrographic recording medium. A toner application unit feeds electrostatically charged toner particles into the space between the development electrode arrangement and the charge retaining surface of the recording medium. The development electrode arrangement is comprised of an array of electrode segments each segment being electrically isolated from each other segment and each segment being allowed to float electrically. The floating electrode segments are so arranged that every element of the recording medium that is subjected to the toning process passes over at least one electrode segment during the toning process.

Abstract: Disclosed is a laser-imagable material comprising a transparent film having thereon a dried coating comprising graphite particles and binder. Also disclosed is the method of making the laser-imagable material and the method of imaging it.

Abstract: An apparatus for transporting a recording medium, such as transparent electrophotographic film, which has a conductive layer, from a supply to a take-up roll. The apparatus includes a drive roller that has a conductive ring. The conductive layer of the film is maintained at a desired potential, generally ground, and a different potential is applied to the conductive ring of the drive roller. When the film contacts the periphery of the drive roller, an electrostatic attractive force is developed between the conductive ring of the drive roller and the conductive layer of the film, thereby allowing the drive roller to transport the film without slip.

Abstract: An improved electrographic recording apparatus and method. An electrographic recording medium has a charge retaining front surface on which charge is distributed in a pattern representing a desired image to be recorded, and a field permeable conductive layer. While charge is being deposited on the charge retaining surface of the electrographic medium, a field is established and maintained behind the rear surface of the medium, said field penetrating the conductive layer and having a field strength on the charged side of the medium that opposes a field that causes charge to be deposited on the charge retaining surface of the medium. In another aspect of this invention, the recording apparatus has a toner application station that is located apart from the charge depositing means, and a second field, having the same polarity as the first field, is established and maintained behind the rear surface of the electrographic medium at the toner station.

Abstract: An improved electrographic recording system. The system includes a first charging corona for providing a distribution of charge on a surface of a recording medium representing a desired image to be recorded on the medium. The system also includes an automatically controlled second charging corona. A sensor continuously monitors the potential of a conductive layer of the medium and automatically controls the magnitude of the charge deposited by the second charging corona so as to maintain a constant potential at the conductive layer of the medium.