Information recording patch, printed sheet, and authenticity discrimination method therefor

Abstract

This invention provides an information recording patch that allows accurate authenticity discrimination, a printed sheet, and an authenticity discrimination method therefor. An information recording patch includes a protective layer (), intermediate layer (), metal layer (), and adhesive layer (). The protective layer () made of a material having a predetermined dielectric constant is arranged at the uppermost layer. The intermediate layer () made of a material having a predetermined dielectric constant has, on its surface, a three-dimensional pattern corresponding to the design of a hologram forming layer including the intermediate layer and the metal layer. The metal layer () made of a material having a predetermined conductivity is arranged on the three-dimensional surface of the intermediate layer to form a conductive film. A mirror surface having a three-dimensional pattern, which is formed by the metal layer and the intermediate layer, serves as the main component of the image of the hologram forming layer. The adhesive layer () made of a material having a predetermined dielectric constant has the characteristic of a dielectric of itself. When this information recording patch was measured using a leakage microwave sensor, the detected voltage exhibited 'medium level' in the conductive region of the metal layer and 'low level' in the remaining regions.