Protective coating for thermosensitive material

摘要

A protective coating is applied to a thermally reactive material layer in laminate manner. The coating includes a fluorocarbon sizing agent which causes beading of any adverse material and prevents penetration thereof into the thermally reactive material. A combined color developing and dye formulation includes bisphenol, wax, clay and dye in a binder of polyvinyl alcohol which effects a spreading of any adverse material on the surface of the coating.