Patent US 4,480,177

A method of treating paper money and the like for the purpose of identification by applying to one of the surfaces of the paper money a first treating material overcoating the first treating material with a layer of transparent material to prevent the first treating material from being removed from or obscured, and then applying a second treating material over the transparent material and the surface of the paper money where the first and second treating materials are normally invisible but rendered visible under ultra violet light. The method may also include providing means for detection of the paper money by touch, taste, smell or hearing. The invention also contemplates the article produced by the method.