in electro static a paper is treated with a material consisting of zinc oxide combined with a thermoplastic resin.when that paper is kept in the xerox machine.it passes through a corona charging bar. Within the charging bar, the zinc oxide coating picks up a negative electrical charge.
the original document is exposed to light, which reflects off the white portions of the document. Dark portions of the document do not reflect light.Light reflected off the original document is then reflected by a series
of mirrors to the treated copy paper which has been passed into this
section of the machine. Light striking the copy paper removes negative
charges placed by the charged bar, leaving charged sections that
correspond to the absence of light, that is, the dark places on the
original document. so the original document is xerosed into duplicate document.
the exposed copy paper is passed through a toner bath, where
positively-charged toner attaches itself to negatively-charged areas on
the copy paper. When the paper is passed through a pair of rollers, the
toner is pressed into the copy paper, forming a permanent positive image
that corresponds to the image on the original document.
hope this may help you if so plzz mark it as bst