Patent ID: 6109730
Filing Date: 2000-08-29
Classification: B41J,G03G

Abstract:
A direct electrostatic printing method performed in consecutive print cycles, each of which includes at least one development period (t.sub.b) and at least one recovering period (t.sub.w) subsequent to each development period (t.sub.b), the method comprising the steps of:producing a pattern of variable electrostatic fields on a plurality of control electrodes proximate to apertures during at least a part of each development period (t.sub.b) to selectively permit or restrict the transport of charged toner particles from a particle source through said apertures toward a back electrode, said variable electrostatic field for one of said control electrodes having a first polarity to permit transport of toner particles through a respective one of said apertures and having a second polarity to restrict transport of toner particles through said respective one of said apertures; andproducing a supplemental electric field during a first portion of each development period, said supplemental electric field having a polarity selected with respect to said charged toner particles to enhance the transport of toner particles from said particle source toward said back electrode, said supplemental electric field having an insufficient magnitude to cause transport of toner particles through said respective one of said apertures when said plurality of control electrodes for said apertures has said electrostatic field selected to restrict transport of toner particles.