GB1141167A - Xerographic development - Google Patents

Abstract

1,141,167. Electro-photographic apparatus. RANK XEROX Ltd. April 25, 1966 [April 30, 1965], No. 17940/66. Heading G2H. Electroscopic toner is applied to an insulating surface, in the form of a xerographic surface or a donor member which applies the toner to xerographic surface, by flowing the toner and a granular carrier along a path separate from, but adjacent the insulating surface. An electrostatic image on xerographic drum 19, Fig. 1, is developed by cascading toner and carrier down an inclined shoot 64 on to a curved support 66 spaced between 0.03 to 0.12 inches from the drum surface within the field of the electrostatic image. The support 66 is electrically biased relative to drum 19. Toner 28 is added in metered quantities to the mixture by a gate 59. The toner may comprise a copolymer of styrene and n-butylmethacrylate. In a modification. Fig. 2 (not shown), the xerographic surface comprises a belt 70, e.g. of vitreous selenium on a conductive substrate. The image developed by either a single or the duplex units (78) as shown, is transferred to a web (43). In a further modification. Fig. 3 (not shown) a multicolour image is produced on belt (70) by developing with a first colour toner by unit (111), forming an image, and developing with a second colour before transfer to web (43). A plate (86) Fig. 4 (not shown) is developed in a rocking tray (87). Endless donor members (105) Figs.5 and 6 (not shown) are uniformly loaded in the same manner as that described with reference to Fig. 1. A vibrator (108) Fig. 5 (not shown), actuated mechanically, electro-mechanically, Piezo-electrically or acoustically dislodges toner to facilitate attraction to the drum (19).