Machine readable security features
A technology with safety features and safety, applied in the field of safety ink, can solve the problems of limited production complexity, low thermal stability, etc., and achieve the effect of high absorption and high chemical stability
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
Method used
Image
Examples
Embodiment approach
[0166] According to one embodiment, the identification device comprises: a first source (such as a VIS LED) emitting at a first wavelength in the visible light range (400nm to 700nm); a second source (such as a NIR LED) emitting at a first wavelength in the NIR range ( 780nm to 1400nm); and a broadband detector (such as a photomultiplier tube). The first source and the second source emit at time intervals, allowing the broadband detector to output output signals that correspond to VIS emissions and NIR emissions, respectively. The two signals (VIS signal to VIS reference, and NIR signal to NIR reference) can be compared independently. Optionally, the two signals can be converted into a difference (or ratio) value, and the difference (or ratio) value can be compared to a difference (or ratio) reference stored in a database.
[0167] According to another embodiment of the detector unit, and with the aim of increasing the operating speed, said detector may comprise two detectors...
Embodiment
[0175] The invention will now be described in more detail with reference to non-limiting examples. The following examples provide more details on the preparation and use of security inks for printing machine readable security features, which independently comprise IR absorbing materials.
[0176] Four security inks have been prepared and coated on substrates:
[0177] i) oxidatively drying gravure security inks (Examples E1, E2 and Comparative Example C1),
[0178] ii) UV-Vis curable screen printing security inks (Examples E3, E4 and Comparative Example C2),
[0179] iii) heat drying rotogravure security inks (Examples E5, E6 and Comparative Example C3), and
[0180] iv) heat-drying screen printing security ink (embodiment E7, E8 and comparative example C4)
[0181] Among them, E1, E3, E5 and E7 contain anhydrous iron(II) orthophosphate (IR-A 1) with a phosphomanite structure,
[0182] where E2, E4, E6 and E8 contain potassium iron(II) orthophosphate without crystallizatio...
PUM
Login to View More Abstract
Description
Claims
Application Information
Login to View More 


