| 摘要 |
PROBLEM TO BE SOLVED: To restrict unauthorized copying by constituting a medium of an image forming layer and at least one of image forming layers capable of forming a microdot pattern having reduced optical density from the latent image of the microdot pattern. SOLUTION: This medium is constituted of at least one image forming layer 44 supported by a supporting body 46 of a light reflecting paper and at least one of the image forming layers capable of forming the microdot pattern having the reduced optical density from the latent image of the microdot pattern. Namely, silver halide grains 40 sensitized by microdot exposure are arranged at optional positions in a photosensitive image forming layer 44 which is coated and formed on the supporting body 46. In the case of detecting the microdot pattern expressing a document whose copying is restricted, a signal showing the detection of the document whose copying is restricted is turned on and copying processing is stopped by controlling the software of a copying device. |
