Abstract
Wetting is basic to coating. Initially air contacts the solid, and during coating the liquid displaces the air from the moving solid surface so that none is visible in the coated film. Thus, coating is a process of dynamic wetting. For uniform coating, the wetting line must remain straight and advance steadily. At sufficiently high speeds, however, the wetting line becomes segmented and unsteady as a thin air film forms between the solid and liquid. The air film disrupts the uniformity of the coated film, and often air bubbles appear in the coating. Dynamic wetting failure limits coating speed.
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Blake, T.D., Ruschak, K.J. (1997). Wetting: Static and Dynamic Contact Lines. In: Kistler, S.F., Schweizer, P.M. (eds) Liquid Film Coating. Springer, Dordrecht. https://doi.org/10.1007/978-94-011-5342-3_3
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DOI: https://doi.org/10.1007/978-94-011-5342-3_3
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