(1) a picture or design at least part of which is in an invisible or dimly visible state and is so constructed as to become, by intended use, preceptible, or more clearly so, upon appropriate treatment; or (2) material intended to present apparent visible changes in an incorporated design or image when: (a) subjected alternatively to reflected or transmitted light; or (b) viewed on a single face thereof, along different sight lines; or (c) viewed alternatively on each face, and the included image or design is either completely light pervious or substantially identical on each such face.
SEE OR SEARCH THIS CLASS, SUBCLASS:
199, for a product comprising a discontinuous coating which may be latent and developable to indicate attempts at erasure or alteration.
SEE OR SEARCH CLASS
40, Card, Picture, or Sign Exhibiting,
106.51+, for a display including an illusion of motion; subclass 137, for a sign with a changeable reading; and other appropriate subclasses, for a latent image in a display device.
355, Photocopying,
78+, for contact printing. 430, Radiation Imagery Chemistry: Process, Composition, or Product Thereof, appropriate subclasses for radiation imagery compositions, a latent radiation image, and a process of developing an exposed image.
434, Education and Demonstration,
327+, for a latent image the development of which involves the educative process.
472, Amusement Devices, particularly
57+, for an amusement device producing either a physical or optical illusion.
