Drying air-induced disturbances in multi-layer coating systems

摘要

A range of new experimental techniques is developed to quantify drying-air induced disturbances on low viscosityudsingle and multi-layer coating systems. Experiments on prototype slide-bead coating systems show that the surfaceuddisturbances take the form of a wavelike pattern and quantify precisely how its amplitude increases rapidly with wetudthickness and decreases with viscosity. Heat transfer measurements show that the redistribution of water to form anudadditional lower viscosity carrier layer while increasing the solids concentration of the upper layer or layers enablesudthe maximum drying rate, for which drying-air induced surface disturbances are acceptably small, to be increasedudwith significant commercial benefits.