DUPLICATION PREVENTING MEDIUM AND MANUFACTURE THEREOF

摘要

PROBLEM TO BE SOLVED: To provide a printed matter having an effect for preventing forgery by a color copying machine and a method for making the printed matter. SOLUTION: A latent pattern is formed on the surface of a duplication preventing medium by at least two kinds of light reflection parts which are different in reflectance and made evident by a duplicate by a color copying machine. In a method for making the latent pattern, a thin metal film layer 13 is formed on the whole surface of a backing 11, and a light transmission layer 12 for controlling the quantity of transmitted light according to a prescribed pattern is formed. Or, the first light transmission layer 12-1 is formed on the whole surface, and the second light transmission layer 12-2 is formed on the layer 12-1 according to a prescribed pattern.