Processes for in-field hardening of optical effect layers produced by magnetic-field generating devices generating concave field lines
US10052903B2 · kind B2 · utility
1Cited by
16References
25Claims
0Family size
Assignee
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Key dates
| Filing date | Jul 9, 2015 |
| Grant date | Aug 21, 2018 |
| Priority date | — |
| Expiry date | Jul 9, 2035 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB05D3/067
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A method is provided for freezing the orientation of orientable magnetic or magnetizable pigment particles by irradiation hardening the coating layer comprising the orientable magnetic or magnetizable pigment particles through the substrate carrying the coating layer. This method can be used in the protection of security documents, such as for example banknotes and identity documents, against counterfeit and illegal reproduction.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.