Applicator for Electrostatic Deposition Coating of Continuous Moving Web

An applicator for electrostatic deposition of dry powder on a grounded continuous moving electrically conductive web, the applicator comprising:

• a powder feeding system, at least one powder dispenser, an electrostatic deposition chamber, and at least one wire electrode in the electrostatic deposition chamber;
• wherein an opening of a powder dispenser outlet of the at least one dispenser is arranged along a latitude of the electrically conductive web, and a ratio (P) of a width (W) of the opening and a coating width (L) of the electrically conductive web is in a range of about 0.25-1.0 cm;
• wherein the at least one powder dispenser includes a defined angle (α) relative to the electrically conductive web and a vertical distance between the powder dispenser outlet and the electrically conductive web (hd);
• wherein a first wire electrode of the at least one wire electrode generates a corona discharge zone with a radius (R) and is disposed at a vertical distance relative to the electrically conductive web (he);
• wherein the powder dispenser outlet and the first wire electrode are at a horizontal distance (d1);
• and
• wherein the following relationship and condition is satisfied:
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• .