Electrographic copying machine - contg. traps to collect stray toner powder and means for chemically treating the powder collected

摘要

An appts. for forming an image on a receiver sheet (P) comprises an image recording element (2), a unit (9) for forming a latent image on the recording element (2), a unit (4) for developing the latent image on the recording element (2) by means of a developer powder (T), a unit (5) for transferring the developed image to the receiver sheet (P), a unit (7) for cleaning the recording element by removing residual developer powder remaining on the recording element (2) after transfer of the developed image to the receiver sheet (P) by the transfer unit (5) and a housing (1) in which the units (9), (4), (5) and (7) are mounted. The housing (1) also contains a means (21,22,23,24) for catching the developer powder scattered by or falling from the developer unit (4), the transfer unit (5) and/or the cleaning unit (7), and a means for chemically treating the developer powder collected. USE/ADVANTAGE - The units for trapping the stray powder are pref. in the form of plastic or metal containers contg. a sponge or foam type material impregnated with a plasticiser cpd. which is capable of softening or melting the binder resin used in the toner, so that the trapped toner powder becomes adherent and sticks to the powder trap. In this way the interior of the machine remains clean and does not become contaminated with stray powder from the various functional stations in the machine. The individual powder traps can be replaced easily when saturated with trapped powder.