IDENTIFYING MEDIUM AND IDENTIFYING METHOD FOR OBJECT

摘要

An identifying medium (A) for identifying the authenticity of an object by providing an optically identifiable mark on the object. A film (20) having the light reflection layer of polymer cholesteric liquid crystal having in turn a circularly polarized light selectivity of reflecting a specific circular polarized light is fixed to part of the surface of a support (10), and printing is made on the portions other than the film (20) of the support (10) in the same color as that shown when the film (20) is viewed from the front. The identifying medium (A) appears to be red at the support (10) and the film (20) when viewed from the front (although the film has a metallic gloss), but, at a larger viewing angle, the film (20) changes to blue by the blue-shift of polymer cholesteric liquid crystal to show a color different from the support (10) does.