Quantum dot security inks

摘要

A security ink is provided which includes a liquid medium having a plurality of quantum dots disposed therein. Upon excitation with a suitable light source, the ink exhibits a quantum yield greater than 30%, and a photoluminescence which has a lifetime of more than 40 nanoseconds and which varies by at least 5% across the emission spectrum of the quantum dots. Also disclosed are apparatuses for using the same for anti-counterfeit or authentication purposes, which uniquely identifying the presence of photoluminescent materials by spectrally resolving their photoluminescence lifetime.

主权项

1. A security ink, comprising:
a liquid medium; and a plurality of quantum dots disposed in said medium which, upon excitation with a light source, exhibit a quantum yield greater than 30%, and a photoluminescence which has at least one lifetime of more than 40 nanoseconds but less than 1 millisecond and which varies by at least 5% across the emission spectrum of the quantum dots.