A lens pigment suitable for manufacturing value documents by printing technology, includes a carrier substrate which forms a lens base and which is supplied on its front side with a first plastic having at least one elevation that produces a microlens and with a second plastic leveling the first plastic.

A device comprising: an optical emitter for emitting light having an emitted optical spectrum; an optical sensor for receiving light reflected from a tag attached to an object; and a processor configured to: determine a reflected optical colour spectrum of the light reflected from the tag based on an output of the optical sensor; retrieve an optical signature associated with said object from memory; and determine the authenticity of said object based on comparing the optical signature and the reflected optical colour spectrum.

There is described the use of a transparent film comprising a non-fibrous substrate layer of regenerated cellulose in the manufacture of a security article exhibiting printed information, wherein said transparent film is the material on which printed information and optionally one or more other security feature(s) is disposed, and wherein said transparent film exhibits one or more, and preferably all, of the following properties: haze of no more than 10%, preferably no more than 5%, preferably no more than 4%, preferably no more than 2.5%; birefringence of from about 400 to about 800 nm; a surface energy of at least about 38 dynes, preferably at least about 40 dynes, preferably at least about 42 dynes, and preferably no more than from about 60 dynes; and a water vapour permeability in the range of from about 20 to about 40, preferably from about 25 to about 35, preferably from about 28 to about 32 g/m.sup.2/24 hours at 25° C. and 75% relative humidity, and/or in the range of from about 110 to about 130, preferably from about 115 to about 125, preferably from about 118 to about 122 g/m.sup.2/24 hours at 38° C. and 90% relative humidity.

There is described the use of a transparent film comprising a non-fibrous substrate layer of regenerated cellulose in the manufacture of a security article exhibiting printed information, wherein said transparent film is the material on which printed information and optionally one or more other security feature(s) is disposed, and wherein said transparent film exhibits one or more, and preferably all, of the following properties: haze of no more than 10%, preferably no more than 5%, preferably no more than 4%, preferably no more than 2.5%; birefringence of from about 400 to about 800 nm; a surface energy of at least about 38 dynes, preferably at least about 40 dynes, preferably at least about 42 dynes, and preferably no more than from about 60 dynes; and a water vapour permeability in the range of from about 20 to about 40, preferably from about 25 to about 35, preferably from about 28 to about 32 g/m.sup.2/24 hours at 25° C. and 75% relative humidity, and/or in the range of from about 110 to about 130, preferably from about 115 to about 125, preferably from about 118 to about 122 g/m.sup.2/24 hours at 38° C. and 90% relative humidity.

According to a first aspect of the invention, there is provided a method of deriving information from an optically readable security element, the method comprising: optically reading the optically readable security element, the optically readable security element comprising one or more optically readable structures, optically readable in response to excitation of the one or more optically readable structures, the one or more optically readable structures being arranged to interact with one or more proximal structures of the optically readable security element, the interaction being such that an excitation-emission relationship for the one or more optically readable structures interacting with the one or more proximal structures, is different to an excitation-emission relationship for the one or more optically readable structures and the one or more proximal structures in isolation; the reading comprising: determining data indicative of an optical property of the optically readable security element using first emission electromagnetic radiation, emitted in response to first excitation of the one or more optically readable structures; and deriving the information from the determined data.

The present disclosure refers to a method for manufacturing a secured window in an identification card. The method comprising embedding information in a transparent window of the identification card and covering the embedded information with a thermochromic layer on a first side of the transparent window. The thermochromic layer is configured to become substantially transparent when subjected to a level of heat greater than a determined threshold value. In addition the method comprises the step of covering a second side of the transparent window, opposite to the first side, with a further thermochromic layer, the further thermographic layer being configured to become substantially transparent when subjected to a level of heat greater than the determined threshold value, such that the embedded information becomes visible through the transparent window when both sides of the window are exposed to the level of heat greater than the determined threshold value.

The present disclosure refers to a method for manufacturing a secured window in an identification card. The method comprising embedding information in a transparent window of the identification card and covering the embedded information with a thermochromic layer on a first side of the transparent window. The thermochromic layer is configured to become substantially transparent when subjected to a level of heat greater than a determined threshold value. In addition the method comprises the step of covering a second side of the transparent window, opposite to the first side, with a further thermochromic layer, the further thermographic layer being configured to become substantially transparent when subjected to a level of heat greater than the determined threshold value, such that the embedded information becomes visible through the transparent window when both sides of the window are exposed to the level of heat greater than the determined threshold value.

An optically variable security element is provided for securing valuable articles, whose areal expanse defines a z-axis perpendicular thereto, having a reflective areal region that displays at least two appearances that are perceptible from different viewing directions. The reflective areal region includes two relief structures arranged at different height levels in the z-direction and form a lower-lying and a higher-lying relief structure, each of which is furnished with a reflection-increasing coating that follows the course of the relief. The higher-lying relief structure displays a first optically variable effect in a first color, and the lower-lying relief structure is visible through the higher-lying reflection-increasing coating itself, or through grid spaces or gaps in the higher-lying reflection-increasing coating and displays a second optically variable effect in a second, different color. The security element is furnished in an interior layer provided contiguously or in some regions, with at least one machine-readable feature substance.

A data protector according to an embodiment of the present disclosure includes: a data layer configured to record confidential information as a visible image; and one or a plurality of cover layers disposed at least one of above or below the data layer and configured to transition between a color-developed state and a decolored state in a visible wavelength region.

A sheet assembly can be cut into one or more cards. The sheet assembly includes an upper sheet configured to receive a first printing of first indicia for the one or more cards, a polymer core coupled with the upper sheet, and a lower sheet configured to receive a second printing of second indicia for the one or more cards. The lower sheet is coupled with the polymer core with the polymer core disposed between the upper sheet and the lower sheet. The upper sheet, polymer core, and/or the lower sheet is or are formed from a polymer binder with inorganic particles dispersed in the polymer binder. The inorganic particles can have a first density of the inorganic particles that is less than four times a second density of the polymer binder and/or a mass-median-diameter (D.sub.50) of the inorganic particles can be larger than ten microns in size.