Rhone-poulenc Systemes

Donald H Kings

Pham K Quang

Jean-Claude Marckmann

The invention relates to a process and a device for developing a latent image formed on a magnetic surface, by means of a magnetic developing powder, in order to form a powder image. The device contains means (2) for causing the powder (4) to flow onto the magnetic surface (1) uninfluenced by a magnetic field other than that of the magnetic surface (1). These means can consist of magnetic means (3) for taking the powder (4) from a trough (5), means (6) for detaching the powder (4) from the magnetic means (3), and means (7) for bringing the powder (4) into the vicinity of the magnetic surface (1). This developing device can be used in a printing apparatus containing means for transferring a powder image onto a substrate.

Process for developing a latent image formed on a magnetic surface,

This invention provides a process of electrographic reproduction onto an arbitary support, whereby an image of a magnetic, monocomponent developing powder is transferred, under the influence of electrical means, onto a support covered with a thin layer of volatile dielectric liquid having a volume resistivity greater than 10.sup.3 ohm-cm.sup.2 /cm.

Growing community of inventors

St. Nicolas D'Aliermont, France

Donald H Kings