| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a printing base material for inhibiting forgery by copying, for which the identification of a latent image by bare eyes is made more difficult before copying, and the latent image becomes easier to be discriminated after the copying. <P>SOLUTION: This printing base material 1 for inhibiting the forgery by copying has a latent image pattern 2 comprising half tone dots being printed on the surface of the base material, and a background pattern 3 comprising half tone dots being printed around the latent image pattern. In the printing base material 1, for the half tone dots constituting the background pattern 3, a total number of screen lines is set to be within a range of 150 lines to 175 lines, and for the half tone dots constituting the latent image pattern 2, a total number of the screen lines is set to be within a range of 65 lines to 85 lines. Also, the density of the latent image pattern 2 is set to be within a range of 12% to 14%, and the density of the latent image pattern 2 is set to be higher than the density of the background pattern 3, and also, a difference in the density is set to be within 2%. <P>COPYRIGHT: (C)2007,JPO&INPIT</p> |
