| 摘要 |
<p>A substrate bears essentially non-visible image formed from at least two fluorescent and/or phosphorescent inks, both or all of which are capable of being excited by a single band of non-visible radiation. The fluorescent and/or phosphorescent inks upon excitation by the appropriate radiation produce visible radiation of two or more different colors, with differing areas of the non-visible image displaying differing colors, so that a full-color image becomes visible. The substrate may also bear visible indicia, and may have the form of, for example, an identification document or a container for goods.</p> |
