Coating and Solidification (Chapter in Roll‐to‐Roll Manufacturing: Process Elements and Recent Advances)

This chapter covers the coating, drying, and curing processes along with defect management. The first requirement for coating is that the liquid coating must wet the substrate at the interface. The second requirement for successful coating is that the coating applicator must be capable of spreading the liquid across the substrate. The region on the operability diagram that gives uniform coating is called the coating window. The most common pre-metered coating methods are slot die and extrusion coating. This chapter discusses the hardware and issues associated with turning the liquid coating into a dry material that can be wound into a roll without blocking. Infrared drying (IR) is relatively common in the paper and printing industries. UV curing is a common option for crosslinking coatings. There are two other techniques for getting the energy into the coating that should be mentioned: radio-frequency drying and microwave drying.