摘要 |
A coater head has a housing which defines a coating pond supplied with coating under pressure. A plurality of bars extend within the coating pond in the cross-machine direction, and are spaced parallel to one another in the machine direction. A paper web is engaged against a backing roll, and travels through the coating pond past a metering blade which applies coating from the pond to the web. The bars induce a turbulent flow which shears bubbles of air entrained in the coating pond, thereby reducing the bubble diameters and air-induced imperfections in the coating. Greater machine speed, which tends to entrain more air, induces greater shear at the bars which causes bubble size to be more greatly reduced.
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