The present invention relates to 1,6,7,12-tetra-(2-isopropylphenoxy)-substituted perylene tetracarboxylic acid diimides of the formula (I) wherein R.sup.1 and R.sup.2 independently of each other are selected from hydrogen, C.sub.1-C.sub.24-alkyl, C.sub.1-C.sub.24-haloalkyl, C.sub.3-C.sub.24-cycloalkyl, C.sub.6-C.sub.24-aryl and C.sub.6-C.sub.24-aryl-C.sub.1-C.sub.10-alkylene, where the rings of cydoalkyi, aryl, and aryl-alkylene in the three last-mentioned radicals are unsubstituted or substituted as defined in the claims and in the description. Moreover, the present invention relates to the use of said perylene compounds, in particular to the use of said perylene compound(s) in color converters, for data transmission and in security inks for security printing. The present invention also relates to the use of said color converters, to their use in lighting devices, to lighting devices comprising at least one LED and at least said color converter and to a device producing electric power upon illumination comprising a photovoltaic cell and said color converter. ##STR00001##

The present technology relates generally to a stable oil-in-water emulsion containing upconverting nanoparticles. In particular, the present technology relates to an ink formulation comprising a stable oil-in-water emulsion of upconverting nanoparticles useful for security printing. Preferably the upconverting nanoparticles comprise a β-Na(RE)F.sub.4 nanoparticle, wherein RE is a lanthanide, yttrium, or a combination or mixture thereof.

A microcapsule, method, and article of manufacture are disclosed. The microcapsule includes an outer shell, a molecular sensitizer, a molecular annihilator, and an inner shell separating the molecular sensitizer from the molecular annihilator. The method includes forming microcapsules, each microcapsule having an outer shell, a molecular sensitizer, a molecular annihilator, and an inner shell separating the molecular sensitizer from the molecular annihilator. The article of manufacture includes at least one of the microcapsules.

An example container includes: structure having an interior and an exterior. The interior is to contain an electronic product. The exterior comprises: a first label of a first type of polychromatic ink to be activated at a first wavelength; and a second label of a second type of polychromatic ink to be activated at a second wavelength different from the first wavelength; the first label to indicate a first set of features to be configured at the electronic product using a first wireless signal; and the second label to indicate a second set of features to be configured at the electronic product using a second wireless signal. The structure is transparent to the first wireless signal and the second wireless signal.

An intaglio printing ink includes capsule luminescent pigments and a further machine-readable feature substance. The capsule luminescent pigments include at least one core with a luminescent substance and one shell encapsulating the at least one core. They are characterized by their high luminescence intensity and high chemical stability, which enables a simultaneous loading of the intaglio printing ink with a further machine-readable feature. A printing method and a printed product include the intaglio printing ink.

A credential with one or more security features is disclosed. The disclosed credential includes a windowed security feature. The windowed security feature is taught to include a mirror element positioned in proximity with a transparent window and a first photo-luminescent feature positioned relative to the transparent window and the mirror element such that the mirror element enhances a luminescence of the first photo-luminescent feature when viewed and illuminated through the transparent window.

Described herein is an ink containing a security element, methods of using the ink, and items produced using the ink. For example, herein is disclosed a method for forming a layer on an item, the method comprising depositing on the item an ink containing a security element and a species for forming a metal matrix to form the layer, which comprises a metal matrix having embedded therein the security element.

To print a security feature on a medium a method is suggested, comprising inkjet printing an ink including one or more pigments, wherein at least one pigment satisfies the formula $\frac{\mathrm{\pi \Delta \rho }{\mathrm{gd}}^4}{12k_{B}T}>1$
and whereas Δρ is the density difference between pigment and ink vehicle; g is the earth acceleration constant; d is the pigment particle diameter D90; k.sub.B is the Boltzmann constant; and T is the temperature. Inkjet printing of the ink is performed by a flextensional ink jet print head structure and printing is performed to provide one or more security features on the medium.

A security device includes a substrate and a photoluminescent image on or in the substrate. The image includes at least two different visible light emitting photoluminescent quantum dot compositions, each arranged according to different respective photoluminescent sub-images. The at least two different visible light emitting photoluminescent quantum dot compositions have different emission spectra from one another, and the same or different excitation spectra. The at least two different visible light emitting photoluminescent quantum dot compositions emit different respective visible colours from one another when excited. The respective photoluminescent sub-images are configured such that the photoluminescent image formed by the combination of the respective photoluminescent sub-images is multi-coloured, emitting different visible colours in different laterally offset parts thereof upon excitation of the at least two different visible light emitting photoluminescent quantum dot compositions. At least a portion of the photoluminescent image overlaps an at least semi-transparent region of the substrate.

The objective of the present invention is to provide an information recording body, a medium and a printed product having improved design properties. An information recording body provided with a superimposed image including a brilliant layer and a transparent layer formed on the brilliant layer is characterized in that: the brilliant layer is a chromatic color image formed from a brilliant material; the transparent layer is a regular pattern image formed from a transparent starting material; the transparent starting material is configured in such a way that an amount of light reflected therefrom differs depending on an observation angle; and the superimposed image is formed in such a way that the transparent layer is recognizable in accordance with a specific observation angle.