A large number of coatings have been described which serve very specific purposes. An example is a foam coating which may be applied by spraying, dipping, or other normal procedures. On curing, however, there is sufficient gas generation to foam the coating. A fine cellular structure results. The resulting layer is thick but light and has a very high strength‐to‐volume ratio as well as insulating properties [Downey Finishing Corp., 1629 S. 55th Ave., Cicero, IL 60650].