| 摘要 |
<p>PROBLEM TO BE SOLVED: To discriminate copy readily by permitting the first and second patterns to be formed in such a way that crossed parts of straight lines enlarge easily through copying, and are reproduced with thick density in copy preventive printed matter with latent images formed by an image line formation of the first and second patterns. SOLUTION: Latent images are formed by an image line formation of the first and second patterns, in which the first pattern is formed by unit rectangular image lines I and groups of straight lines 1-3 crossing with the unit rectangular image lines I and a group of straight lines 3' not crossing therewith in the unit rectangular image lines I, and the second pattern is formed by unit rectangular image lines I' formed by groups of straight lines 4, 5 not crossing with the unit rectangular image lines I in the unit rectangular image lines I. Furthermore, the formation is made such that each image line area of the groups of the straight lines 1-3 and image line area of the straight lines 4, 5 is made the same, and the groups of the straight lines 1-5 are put in the same angle and the same direction. When such a print pattern is printed and the printed matter are copied, an enlargement of the image lines and deformation of image lines are created at the intersections of oblique lines 1-3, so that it can be found visually as duplicated matter, i.e., a counterfeit.</p> |
