Active Biased Electrodes for Reducing Electrostatic Fields Underneath Print Heads in an Electrostatic Media Transport

摘要

Embodiments described herein are directed to a system for reducing electrostatic fields underneath print heads in a direct marking printing system. The system includes: one or more print heads for depositing ink onto a media substrate; a media transport for moving the media substrate along a media path past the one or more print heads; a conductive platen contacting the media transport belt; an electrostatic field reducer that includes an alternating current charge device positioned upstream of the one or more print heads; and one or electrically isolated biased electrodes in registration with the ink deposition areas of the one or more print heads. The media transport includes a media transport belt and, when the media is on the transport belt it has an electrostatic field, which can cause printing defects. The electrostatic field reducer and electrodes reduce the electrostatic field on the surface of the media and thereby reduce printing defects.

主权项

1. A system for reducing electrostatic fields underneath print heads, the system comprising:
one or more print heads for depositing ink onto a surface of a media substrate in one or more ink deposition areas; a media transport for moving the media substrate along a media path in a process direction past the one or more print heads, wherein the media transport comprises a media transport belt, and wherein the media has an electrostatic field; a conductive platen contacting the media transport belt, wherein the conductive platen has one or more apertures; and one or more electrically isolated biased electrodes positioned in the one or more apertures and corresponding to the locations of the one or more ink deposition areas of the one or more print heads, and wherein each of the one or more electrically isolated biased electrodes extends in the process direction and in a trans-process direction; and one or more voltage sources for providing a voltage to the one or more electrically biased electrodes, wherein the voltage is provided to the one or more electrically biased electrodes to reduce the electrostatic field on the surface of the media receiving the ink.