PIGMENTS HAVING A VIEWING ANGLE DEPENDENT SHIFT OF COLOR, METHOD FOR PRODUCING SAID PIGMENTS, USE OF SAID PIGMENTS IN SECURITY APPLICATIONS, COATING COMPOSITION COMPRISING SAID PIGMENTS AND A DETECTING DEVICE
US6695905B2 · kind B2 · utility
22Cited by
18References
28Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Aug 14, 2002 |
| Grant date | Feb 24, 2004 |
| Priority date | — |
| Expiry date | Aug 14, 2022 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC09C2220/20
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
The invention describes luminescent optically variable pigments (OVP), methods for obtaining such pigments, as well as the use of such pigments as security elements in inks, coatings and articles. The luminescence centers are preferably incorporated into the dielectric material of the OVP's optical<i>Fabry-Perot</i> resonance cavity, allowing for the machine-discrimination of luminescent OVP from simple mixtures of luminescents and non-luminescent OVP.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.