摘要 |
<p>Method and apparatus for establishing a uniform charge level on a randomly charged web having both positive and negative, bounded and/or free electrostatic charges. The method and apparatus include first and second uniform electrostatic fields of different magnitudes and of opposite polarities that are spaced from one another. Apparatus is provided for passing the randomly charged web through the first electrostatic field with a particular magnitude and polarity to either neutralize or change the polarity of either the positive or negative electrostatic web charges and then subsequently through the second electrostatic field with its different magnitude and its opposite polarity to either neutralize or change the polarity of the web charge present after exiting from the first electrostatic field to thereby adjust the electrostatic charge level to the desired uniform magnitude.</p> |