Browse Prior Art Database

Original Publication Date: 1986-Oct-31
Included in the Prior Art Database: 2004-Apr-04

Publishing Venue

Xerox Disclosure Journal


Passive brush type static eliminators have been rapidly growing in commercial acceptance as effective low cost devices to control residual static levels on xerographic copies. It is desired however to avoid use of conductive carbon fibers since any shedding of such fibers may tend to contaminate high voltage components i n e lecros ta to gr a p h i c repro d u c-n g apparatus . Accordingly, resistive carbon fiber brushes having D C volume resistivities as high as 1 x 106 ohm-cm have been used However high resistivity fibers tend to increase significantly in resistance with age thereby potentially limiting their functional life Acceptable static control may be defined as a residual charge on a copy sheet exiting the eliminator device being less than 20 nanocoulombs per 83 by 11 inch copy sheet. Paper being transported through the xerographic process is preferentially charged to a negative polarity rather than a positive polarity By the application of a relatively low positive bias (from about 100 to 400 volts) to a high resistance carbon fiber static eliminator brush a significant reduction in absolute levels of static on the copies is achieved Further a series resistor may be used to assure acceptable safe brush current levels in the event of accidential nperator contact In addition the resistive fibers serve to prevent coIlapse of the brush field upon incidental contact of individual fibers to ground