Methods and systems for optical effects in pigments, inks, and on media. One aspect of this disclosure involves a pigment particle which includes a core, having a fluorescent material and having a spherical shape, and a shell surrounding the core; the shell includes a photochromic material which has a first optical property in a first light source and a second optical property in a second light source which includes a set of wavelengths not sufficiently present in the first light source. The second optical property attenuates an emitted radiation from the fluorescent material. Other aspects are also described.

Methods and systems for optical effects in pigments, inks, and on media. One aspect of this disclosure involves a pigment particle which includes a core, having a fluorescent material and having a spherical shape, and a shell surrounding the core; the shell includes a photochromic material which has a first optical property in a first light source and a second optical property in a second light source which includes a set of wavelengths not sufficiently present in the first light source. The second optical property attenuates an emitted radiation from the fluorescent material. Other aspects are also described.

A system for printing documents and anti-forgery security papers especially banknotes is provided. The system includes a mechanical feeding mechanism, a hologram pattern print section, an invisible, fluorescence color and main colors pattern printing section using at least three units of ink jet, a varnish coating section, a rotating cylindrical silkscreen printing section for optical variable ink (OVI), a raised printing section, a delivery section, a paper and handle receiving section and a central computer control section. The system has been introduced to create various security features in securities wherein all of the processes including the raised printing are introduced in an all-in-on device.

The present invention firstly relates to a security feature for a security or value document. The security feature comprises a zinc sulfide lurninophore in the form of particles. The zinc sulfide lurninophore has the general chemical formula ZnS: Cu.sub.x, M.sub.y, X.sub.z; here, M represents one or more elements from a group comprising the chemical elements Co, In and Ni; X represents one or more elements from a group comprising the halides F, Cl, Br and I; and the following applies: 0 < x < 0.002 and 0 ≤ y < 0.00015 and 0 ≤ z < 0.00050. The particles each have cubic phase portions and hexagonal phase portions. When excited by an electrical field, the zinc sulfide luminophore emits a first radiation in the range of the light spectrum between 580 nm and 780 nm. When excited by heating the luminophore to a temperature between 100° C. and 150° C., the zinc sulfide luminophore emits a second radiation in the light spectrum. Furthermore, the invention relates to a security and value document, which may for example be a bank note or a passport, an identity card, a driving license or a postage stamp. The invention also relates to a method for detecting and/or verifying the security feature according to the invention.

The present invention firstly relates to a security feature for a security or value document. The security feature comprises a zinc sulfide lurninophore in the form of particles. The zinc sulfide lurninophore has the general chemical formula ZnS: Cu.sub.x, M.sub.y, X.sub.z; here, M represents one or more elements from a group comprising the chemical elements Co, In and Ni; X represents one or more elements from a group comprising the halides F, Cl, Br and I; and the following applies: 0 < x < 0.002 and 0 ≤ y < 0.00015 and 0 ≤ z < 0.00050. The particles each have cubic phase portions and hexagonal phase portions. When excited by an electrical field, the zinc sulfide luminophore emits a first radiation in the range of the light spectrum between 580 nm and 780 nm. When excited by heating the luminophore to a temperature between 100° C. and 150° C., the zinc sulfide luminophore emits a second radiation in the light spectrum. Furthermore, the invention relates to a security and value document, which may for example be a bank note or a passport, an identity card, a driving license or a postage stamp. The invention also relates to a method for detecting and/or verifying the security feature according to the invention.

Transaction and identification cards formed from raw bamboo assemblies including one or more raw bamboo layers optionally adhered to a paper backer. In one embodiment, a single raw bamboo assembly is adhered to a base or core substrate. Optionally, a second bamboo assembly is coupled to the first bamboo assembly, with or without a core layer sandwiched in between the bamboo assemblies, such that the card's top face includes a first bamboo layer and the card's bottom face includes a second bamboo layer. One or more image or graphic layers are then either printed directly onto the raw bamboo layer or laminated thereto. Optional protective substrates, films, or coatings are applied to or over the bamboo assembly to protect by sandwiching the one or more ink or printed layers between the protective layer and the raw bamboo layers.

Transaction and identification cards formed from raw bamboo assemblies including one or more raw bamboo layers optionally adhered to a paper backer. In one embodiment, a single raw bamboo assembly is adhered to a base or core substrate. Optionally, a second bamboo assembly is coupled to the first bamboo assembly, with or without a core layer sandwiched in between the bamboo assemblies, such that the card's top face includes a first bamboo layer and the card's bottom face includes a second bamboo layer. One or more image or graphic layers are then either printed directly onto the raw bamboo layer or laminated thereto. Optional protective substrates, films, or coatings are applied to or over the bamboo assembly to protect by sandwiching the one or more ink or printed layers between the protective layer and the raw bamboo layers.

An easily producible security feature according to the invention contains at least one luminescence device on and/or in a product carrier. Additionally, the security feature contains, in and/or on the product carrier, at least one absorptive spectral filter for luminescence radiation exiting from the at least one luminescence device, such that a color impression results both under illumination with visible radiation and under luminescence illumination conditions.

Self-cleaning banknotes are provided using coatings, inks and additives which are photo-active and catalytic to reactions which are effective in breaking up organic contaminants or dirt to allow for the self-cleaning of banknotes by ambient light exposure as well as the cleaning of processed banknotes using equipment with more intense optical excitation, thus increasing their usable life. The invention is usable with all substrates and particularly polymeric substrates such as biaxially-oriented polypropylene (BOPP). The invention further discloses a system which allows a certain class of fitness parameters to cause these banknotes to be redirected to a cleaning module, be revaluated, and then either returned to circulation or rejected and/or destroyed. In addition, inks which are photo-catalytic can be used for extending the life of the banknotes in printed regions.

Self-cleaning banknotes are provided using coatings, inks and additives which are photo-active and catalytic to reactions which are effective in breaking up organic contaminants or dirt to allow for the self-cleaning of banknotes by ambient light exposure as well as the cleaning of processed banknotes using equipment with more intense optical excitation, thus increasing their usable life. The invention is usable with all substrates and particularly polymeric substrates such as biaxially-oriented polypropylene (BOPP). The invention further discloses a system which allows a certain class of fitness parameters to cause these banknotes to be redirected to a cleaning module, be revaluated, and then either returned to circulation or rejected and/or destroyed. In addition, inks which are photo-catalytic can be used for extending the life of the banknotes in printed regions.