Magnetic thin film interference device or pigment and method of making it, printing ink or coating composition, security document and use of such a magnetic thin film interference device
US6875522B2 · kind B2 · utility
28Cited by
7References
21Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Feb 14, 2002 |
| Grant date | Apr 5, 2005 |
| Priority date | — |
| Expiry date | Feb 16, 2022 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/32
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
The invention discloses magnetic OVP, said pigment consisting of thin-layer flakes having a basic metal-dielectric-metal structure to result in a viewing-angle dependent color appearance, and having, in addition to said viewing-angle dependent color appearance, incorporated magnetic properties, to make them distinguishable from OVP of similar appearance but not having said magnetic properties. The invention discloses as well methods for obtaining such pigments and the use of such pigments as security elements in inks, coatings and articles.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.