| 摘要 |
<P>PROBLEM TO BE SOLVED: To offer a laser marking method of valuable security documents based on the interaction of laser irradiation and the of printing ink system to be used. <P>SOLUTION: The laser marking method of valuable security documents is characterized as that at least one sort of printing ink or a system of printing ink layers is applied to the base substrate, and at least one of the aforementioned printing ink or the system of printing ink layers includes a laser photosensitive component, and the aforementioned ink is removed selectively by laser, and if necessary, minute engravings and/or images are additionally formed by laser in the above-mentioned area where the ink is selectively removed. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
