A method for marking a product (1) with a photoluminescent mark, said mark comprising a photoluminescent portion (10) which is transparent under normal light conditions and revealed by photoluminescence under UV illumination, said mark further comprising a non photoluminescent portion (9) which is transparent under normal light conditions as well s under UV illumination, said method comprising: deposing on said product a stack, said stack comprising alternatively layers (2,4) such as AIN, with a thickness of less than 1 micron and layers (3) of a second material, such as GaN with a thickness of less than 10 nm; raising the transparency of said non photoluminescent portion (10) with a deposition of transparent material (6) or incorporation of ions into said non photoluminescent portions.

A method for marking a product (1) with a photoluminescent mark, said mark comprising a photoluminescent portion (10) which is transparent under normal light conditions and revealed by photoluminescence under UV illumination, said mark further comprising a non photoluminescent portion (9) which is transparent under normal light conditions as well s under UV illumination, said method comprising: deposing on said product a stack, said stack comprising alternatively layers (2,4) such as AIN, with a thickness of less than 1 micron and layers (3) of a second material, such as GaN with a thickness of less than 10 nm; raising the transparency of said non photoluminescent portion (10) with a deposition of transparent material (6) or incorporation of ions into said non photoluminescent portions.

Disclosed embodiments may relate to a time-dependent color-changing label for a product. The label may include a first layer comprising a plurality of particles, the particles comprising a time dependent color-changing material that changes color after a predetermined time period, the predetermined time period being greater than one month. The label may also include an attachment structure attaching the first layer to the product. In certain embodiments, the first layer may include a polymer, and the particles may include glass microspheres containing the time-dependent color changing material. The particles may be embedded in the polymer.

A feature substance is provided for securing the authenticity of documents of value, having at least one luminescent substance in particle form and nanoparticles enveloping the surfaces of the luminescent substance particles at least partially, wherein the properties of the feature substance result from the interaction of the properties of the luminescent substance and of the nanoparticles. The invention furthermore relates to a method for producing the feature substance, a method for securing the authenticity of a security element or document of value using a feature substance, as well as security elements and documents of value with authenticity features on the basis of the feature substance.

A feature substance is provided for securing the authenticity of documents of value, having at least one luminescent substance in particle form and nanoparticles enveloping the surfaces of the luminescent substance particles at least partially, wherein the properties of the feature substance result from the interaction of the properties of the luminescent substance and of the nanoparticles. The invention furthermore relates to a method for producing the feature substance, a method for securing the authenticity of a security element or document of value using a feature substance, as well as security elements and documents of value with authenticity features on the basis of the feature substance.

Disclosed are a stereoscopic magnetic print film formed using magnetic particles and a method of manufacturing the stereoscopic magnetic print film. The method includes preparing magnetic ink including magnetic particles, forming a printing layer on a base layer using the prepared magnetic ink, and forming a stereoscopic pattern by applying a magnetic field to the printing layer.

The invention relates to a security pigment of core-shell particles with an organic or metalorganic feature substance, in particular luminescent feature substance, present in dissolved or finely distributed form in the core. The invention further relates to a method for producing the core-shell particles and value documents having the core-shell particles.

The invention relates to a security pigment of core-shell particles with an organic or metalorganic feature substance, in particular luminescent feature substance, present in dissolved or finely distributed form in the core. The invention further relates to a method for producing the core-shell particles and value documents having the core-shell particles.

The present invention relates generally to a data carrier and a method for making the data carrier. More particularly, this invention relates to color laser marking of article, especially security documents. The present invention proposes a security document comprising a multilayers assembly instead of a single color component mixture in a layer. The multilayer assembly comprises at least two laser sensitive layer. Each layer comprises at least one coloring agent component. The order arrangement of the multilayers of bleachable coloring agent component is made so that each layer behaves as a wavelength filter configured to selectively transmit longer wavelengths and block or attenuate shorter wavelengths while protecting the underneath coloring agent component from bleaching interference.

A secure multilayer structure, in particular for a secure document, including a base layer, at least one masking layer including a window opened in the masking layer, the window having an edge, a security element including a photoluminescent agent positioned between the base layer and the masking layer, adjacent to the window edge, such that the presence of the agent can be checked by illuminating the edge of the window and viewing the re-radiated luminescent light emerging from the masking layer through the window edge.