Gas Activated Changes to Light Absorption and Emission Characteristics for Security Articles

摘要

Disclosed are security articles and methods and systems for authenticating security articles using a plurality of stimuli. According to one embodiment, an illustrative security feature includes an encoded feature wherein differential activation of phosphorescent or fluorescent materials creates a machine readable code through the simultaneous presence of a source of electromagnetic radiation and a specific gas environment. A detector detects a differential spectral emission across the security feature that results from the change in gas environment. The spectral emission may be compared to an expected emissive signature to determine authenticity of the security article.

主权项

1. A security article, comprising:
a host material comprising a gas-activated security feature incorporated upon or within the host material; and a gas impermeable layer selectively applied over said gas-activated security feature leaving portions of said gas-activated security feature exposed, wherein the gas-activated security feature is capable of emitting a first spectral emission that changes to a second spectral emission as said exposed portions upon exposure to a change in gas environment of the gas activated security feature.