| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a copy preventing printed material which can indicate a fraudulent copy even when the copy is created by a copy machine with improved performance. <P>SOLUTION: The copy protection printed material P includes a first copy preventing portion 1 having a first background 11 and a first pattern 12 formed on the first background 11, and a second copy preventing portion 2 that has a second background 21 and a second pattern 22 formed on the second background 21, the first pattern 12 has a portion having higher concentration than the first background 11 and a portion having lower concentration than the first background 11, which are adjacent to each other, the second background 21 and the second pattern 22 have different numbers of screen lines of halftone dots, and have the same or substantially the same screen concentration, and, when copy is performed at a concentration equal to or lower than a first concentration, the first copy preventing portion 1 is not copied, and, when copy is performed at a second concentration which is higher than the first concentration, the second pattern 22 of the second copy preventing portion 2 is copied with higher concentration than the second background 21. <P>COPYRIGHT: (C)2013,JPO&INPIT</p> |
