Patent · US Expired

Secured documents identified with anti-stokes fluorescent compositions

US6686074B2 · kind B2 · utility

14Cited by

9References

15Claims

0Family size

Assignee

BUNDESDRUCKEREI GMBH · DE

Inventors

Oliver Muth · Berlin, DE
Helge Brockmann · Bonndorf, DE
Wolfgang Schmidt · Frankfurt, DE
Anett Bailleu · Berlin, DE
Gabriele Brauer · Berlin, DE
Manfred Paeschke · Wandlitz, DE
Benedikt Ahlers · Berlin, DE
Arnim Franz-Burholz · Falkensee, DE
Hans Zerbel · Berlin, DE

Key dates

Filing date	Mar 18, 2002
Grant date	Feb 3, 2004
Priority date	—
Expiry date	Mar 18, 2022

Classification

Technology area (CPC Y)Emerging Cross-Sectional Technologies
CPC primaryY10T428/31678
WIPO fieldTextile and paper machines
WIPO sectorMechanical engineering

Abstract

The present invention provides a secured document including a composition capable of anti-Stokes fluorescence containing an ion capable of absorption of electromagnetic radiation, an ion capable of emitting electromagnetic radiation, and a matrix composition comprising gadolinium, yttrium, lanthanum, and thulium, wherein the wavelength of the absorbed electromagnetic radiation is shorter than the wavelength of the emitted of the absorbed electromagnetic radiation, and wherein the concentrations of the absorbing and emitting ions are adjusted to achieve concentration quenching of anti-Stokes luminescence.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.