摘要 |
A method for electrostatically assisting in coating a liquid composition from a hopper to a web supported by a backing roller, characterized by the steps of a) neutralizing all charges on both surfaces of the web by passing the web through an appropriate electrostatic environment ahead of the coating point, and b) providing a uniform electrostatic field around the backing roller, which field extends through the web to engender an electrostatic "pressure" for urging the liquid composition toward the coatable surface of the substrate at the coating point resulting in an increase in the maximum coating speed achievable without onset of air entrainment at the coating point, improved thickness uniformity of coating, and a reduction in residual charge on the web after coating.
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