Articles, methods of validating the same, and validation systems employing decay constant modulation

摘要

Articles, methods of validating the articles, and validating systems are provided herein. In an embodiment, an article includes a substrate and a security feature on the substrate. The security feature includes a first region that has a first ink composition and a second region that has a second ink composition. The first ink composition includes a first luminescent phosphor and the second ink composition includes a second luminescent phosphor that is different from the first luminescent phosphor. The first luminescent phosphor and the second luminescent phosphor have indistinguishable excitation energy wavelengths, indistinguishable emission wavelengths, and distinguishable temporal decay properties.

主权项

1. An article comprising:
a substrate; and a security feature on the substrate, wherein the security feature includes:
a first region having a first ink composition comprising a first luminescent phosphor; anda second region having a second ink composition and comprising a second luminescent phosphor different from the first luminescent phosphor;wherein the first luminescent phosphor and the second luminescent phosphor have indistinguishable excitation energy wavelengths, indistinguishable emission wavelengths, and distinguishable temporal decay properties.