| 摘要 |
A method and apparatus are provided for controlling the width and improving edge thickness uniformity of a layer of coating material electrostatically deposited on a moving web surface. The apparatus preferably includes a coating applicator, a rotatably mounted web-supporting backing roll spaced therefrom and a source of electrical power coupled between applicator and backing roll for generating a coating material charging and transporting electrostatic field capable of transporting the charged coating material from the applicator to a web surface as the web moves between applicator and backing roll for web coating purposes. The apparatus additionally includes a pair of electrodes coupled to a source of electrical power and mounted in an opposed relation on opposite sides of the charged coating material moving between the coating applicator and the web surface spaced therefrom. Electrode potential is adjusted to a level that will interact with the charged coating material passing therebetween and thereby cause a layer of coating material of predetermined width and improved edge thickness uniformity to be deposited on a selected portion of a moving web surface.
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