A near-infrared-absorption white material, a method of manufacturing the same, and uses thereof. The near-infrared-absorption material includes copper pyrophosphate compound. The copper pyrophosphate compound has a brightness (CIE L*) value of 90 or more in a visible-ray region and is excellent in particle manufacturing properties, and a crystalline structure of the copper pyrophosphate compound is made chemically stable using a heat treatment at a high temperature. The copper pyrophosphate compound is represented by the following chemical formula:

Cu.sub.2P.sub.2O.sub.7 or Cu.sub.2P.sub.2O.sub.7.XH.sub.2O (x=13).

A paper roll, in which a paper strip is wound in the form of a roll, includes a marker formed of a medium containing a phosphorescent material on an end portion of the paper strip that extends from a finishing end of the paper roll to a position that is a predetermined length from the finishing end. A printer includes a roller configured to convey paper supplied from the paper roll, a printing head configured to print information on the paper conveyed by the roller, one or more ultraviolet light emitting diodes (LEDs) positioned downstream of the printing head in a conveyance direction of the paper, and a control unit configured to turn on the LEDs to irradiate the paper on which the information has been printed and discharged out of the printer.

An article comprising a substrate which carries a doped tin oxide wherein less than 50 mol % of the tin atoms in the tin oxide are substituted with a dopant element.

An article comprising a substrate which carries a doped tin oxide wherein less than 50 mol % of the tin atoms in the tin oxide are substituted with a dopant element.

A method for the secure protection of a portion of the surface of an official document bearing markings, in which: a transparent security layer (17) is selected, the layer including at least one semi-transparent printed image including at least one transparent binder and at least one thermochromic pigment (14, 13, 12, 11); the semi-transparent printed image reveals at least one semi-transparent visible pattern in a first non-activated state at least a first temperature, such that the markings can be seen through the image, the pattern not being visible in a second activated state at least a second temperature different from the first temperature. A device for the secure protection of a portion of the surface of an official document and such an official document are also described.

A method for applying a security device (e.g., a micro-optic security thread) to a fibrous web during manufacture is provided. By way of the inventive method, the security device is preferably applied onto the fibrous web at or near a couch roll or similar tool of a paper machine when the fibrous web constitutes a sufficiently consolidated, fully formed wet web. Papers made in accordance with the inventive method, when subjected to the Circulation Simulation Test, showed minimal damage at the paper/security device interface. Moreover, the surface-applied security devices showed acceptable levels of intaglio ink adhesion, and the papers had higher cross-direction (CD) tensile strength and much less show-through on opposing sides thereof.

A method for applying a security device (e.g., a micro-optic security thread) to a fibrous web during manufacture is provided. By way of the inventive method, the security device is preferably applied onto the fibrous web at or near a couch roll or similar tool of a paper machine when the fibrous web constitutes a sufficiently consolidated, fully formed wet web. Papers made in accordance with the inventive method, when subjected to the Circulation Simulation Test, showed minimal damage at the paper/security device interface. Moreover, the surface-applied security devices showed acceptable levels of intaglio ink adhesion, and the papers had higher cross-direction (CD) tensile strength and much less show-through on opposing sides thereof.

Core-shell nanoparticles comprises a phosphorescent core and metal shell comprising at least two metals The phosphorescent core may comprise an up converting phosphor. The phosphorescent core may comprise a trivalent rare earth cation. The phosphorescent core further may comprise a monovalent alkali metal. The phosphorescent core may optionally comprises a second and also optionally a third trivalent rare earth cation.

Core-shell nanoparticles comprises a phosphorescent core and metal shell comprising at least two metals The phosphorescent core may comprise an up converting phosphor. The phosphorescent core may comprise a trivalent rare earth cation. The phosphorescent core further may comprise a monovalent alkali metal. The phosphorescent core may optionally comprises a second and also optionally a third trivalent rare earth cation.

Disclosed herein are devices that change their appearance and/or physical properties when under an external influence, and methods for their production and use. Such devices may be used as features of any type of items, documents, billboards, posters, display devices, advertisements and other items etc. and may be adapted to include decipherable content. Such devices also afford new techniques for a user to check quickly and easily whether the item is a legitimate or a counterfeit copy, either by hand-manipulation of the device, or with the assistance of an additional screening tool.