According to one example, there is provided a visual security feature. The visual security feature comprises a security feature printed on a media. The security feature includes a security code printed on the media, and a holographic image is embossed on the printed security feature.

The present invention relates to perylene bisimides with rigid 2,2-biphenoxy bridges which are useful in a wide variety of applications and to novel to perylene bisimides with rigid 2,2-biphenoxy bridges. The present invention also relates to the use of said compound(s) in color converters for improving the luminous efficacy of LEDs, to color converters and their use and to lighting devices comprising at least one LED or OLED and at least one color converter. The present invention also relates to a printing ink formulation for security printing comprising at least one perylene bisimide with rigid 2,2-biphenoxy bridges and security documents.

Disclosed is a structure for preventing counterfeit, falsification or reuse, including a metal layer, a photoconversion pattern layer including a plurality of photoconverting nanoparticles formed on the metal layer, a metal pattern layer placed on the metal layer and the photoconversion pattern layer, and an adhesive film placed on the metal pattern layer. Accordingly, the structure for preventing counterfeit, falsification or reuse according to the present disclosure allows a pattern indicating a genuine product to be easily identified with an eye through infrared light irradiation, and is fundamentally impossible to re-assemble after deformation of the structure caused by disassembly of a packaging container, thereby preventing counterfeit, falsification or reuse.

Improving the adhesion of a laminate on a plastic card where the laminate overlays a print receptor layer. The size of the laminate is made larger than the print receptor layer so that at least a portion of the perimeter edge of the laminate extends beyond the perimeter edge of the print receptor layer so that the portion of the perimeter edge is adhered or otherwise bonded directly to the surface of the plastic identification document substrate or to other material of or on the plastic identification document substrate other than the print receptor layer. This increases the difficulty in picking the edges of the laminate loose and peeling the laminate from the print receptor layer and from the plastic identification document substrate.

A solid fluorescence standard that can be used to calibrate and/or normalize a device (e.g., a scientific instrument) that is configured for generating and collecting fluorescence data. A fluorescence standard disclosed herein includes an adhesive (e.g., a low viscosity, substantially optically transparent, solvent-free, radiation curable adhesive, such as, but not limited to, a UV curable adhesive), and a selected quantity of fluorescent particles (e.g., quantum dots) dispersed in the adhesive. The adhesive and the fluorescent particles are mixed together and disposed in a sample well. The adhesive is then cured and solidified, which yields a solid fluorescence standard in the well.

Disclosed are optical devices suitable as security devices for document authentication, which comprise at least one two-dimensional array of elongate laser-modified tracks extending within a document substrate that have a distinct optical refractive index compared to the unmodified substrate, which can exhibit excellent diffractive effects. Also disclosed are the use of such devices for document authentication and methods for their production.

An infrared-excited infrared light emitting material and a preparation method thereof, and a security article for anti-counterfeit using thereof relate to a white to pale colored infrared-excited infrared light emitting material, a preparation method thereof, and an ink composition for anti-counterfeit containing the infrared exciting infrared light emitting material which visually appears white or colored, and is excited in the infrared region, emits light in the infrared region, but does not emit light in the visible region, and a security article requiring confirmation of authenticity and anti-counterfeit.

The present invention provides a UV-Vis radiation curable security ink for producing a security feature for securing value documents, wherein said security feature exhibits a blue color upon viewing in transmitted light and a metallic yellow color upon viewing in incident light. The UV-Vis radiation curable security ink comprises a cationically curable or a hybrid curable ink vehicle, and silver nanoplatelets bearing a surface stabilizing agent of general formula (I) ##STR00001## wherein the residue R.sup.A is a C.sub.2-C.sub.4alkyl group substituted with a hydroxy group; the residue R.sup.B is selected from a C.sub.1-C.sub.4 alkyl group, and a C.sub.2-C.sub.4alkyl group substituted with a hydroxy group; and Cat.sup.+ is a cation selected from the group consisting of Na.sup.+, K.sup.+, Cs.sup.+ and Rb.sup.+.

An upconverting pigment dispersion includes an upconverting pigment, such as a -NaYF.sub.4 crystal doped with at least one of Erbium, Ytterbium or Thulium. The upconverting pigment dispersion is aqueous. Upconverting inkjet ink is made by mixing the crystals with a polymer dispersant and water and milling the mixture until the crystal particles are between 50 nanometers and 200 nanometers. Deionized water, a colorant and a humectant are added to the milled mixture.

The present invention relates to a method of manufacturing a substrate with an embedded, UV-visible pattern, wherein a liquid treatment composition comprising at least one acid is deposited onto a substrate, which comprises at least one optical brightener and optionally a filler, wherein the filler comprises 0 to 60 wt.-% of a salifiable alkaline or alkaline earth compound, based on the total weight of the substrate.