A semiconductor nanocrystal include a first I-III-VI semiconductor material and have a luminescence quantum yield of at least 10%, at least 20%, or at least 30%. The nanocrystal can be substantially free of toxic elements. Populations of the nanocrystals can have an emission FWHM of no greater than 0.35 eV.

A copper dopant delivery powder comprising a fused silica powder and a Cu.sub.2S powder. A method of making the copper dopant delivery powder. A method of making a copper-doped glass comprising placing a target glass in a container, packing a composite SiO.CuS dopant powder around the target glass and heating the container and SiO.CuS dopant powder to a temperature of between 800° C. and 1150° C. A copper-doped glass comprising a glass comprising copper-doping wherein the copper-doped glass was formed by covering the glass with a fused silica powder and a Cu.sub.2S powder, wherein the fused silica powder and the Cu.sub.2S powder are mixed in varying ratios of Cu.sub.2S to silica represented by the formula (SiO.sub.2).sub.(1-x)(Cu.sub.2S).sub.x and heating to a temperature of between 800° C. and 1150° C.

A laminated glass luminescent concentrator is provided which includes a solid medium having a plurality of fluorophores disposed therein. In some embodiments, the fluorophore is a low-toxicity quantum dot. In some embodiments, the fluorophore has significantly reduced self-absorption, which allows for unperturbed waveguiding of the photoluminescence over a long distance. Also disclosed are apparatuses for generating electricity from the laminated glass luminescent concentrator, and its combination with buildings and vehicles.

A tube lamp has a tubular portion that serves both as a light guide for energy from a solid state source and as a container for a material bearing a nanophosphor that is pumped by the energy from the source as the energy traverses the light guide. However, the tubular portion of the light guide also allows emission of light produced by the phosphor when excited. The material with the nanophosphor dispersed therein may appear either clear or translucent when the lamp is off and the nanophosphor is not excited by energy from the source.

The present invention relates to the use of nanosystems as non deactivable security markers comprising metal atomic quantum clusters (AQCs) of at least two different size distributions encapsulated in a cavity with an inner diameter less than or equal to approximately 10 nm. These nanosystems are luminescence, particularly fluorescence after external excitation. The invention also relates to security documents, articles or elements incorporating these markers as well as to a method and a system for detecting the same.

The present invention relates to the use of nanosystems as non deactivable security markers comprising metal atomic quantum clusters (AQCs) of at least two different size distributions encapsulated in a cavity with an inner diameter less than or equal to approximately 10 nm. These nanosystems are luminescence, particularly fluorescence after external excitation. The invention also relates to security documents, articles or elements incorporating these markers as well as to a method and a system for detecting the same.

Provided is a scintillator that includes: first phosphors each including an inorganic fluorescent compound; and a second phosphor including a fluorescent resin.

A coating composition includes: (i) a film-forming resin; (ii) an infrared reflective pigment; and (iii) an infrared fluorescent pigment or dye different from the infrared reflective pigment. A multi-layer coating including the coating composition, and a substrate at least partially coated with the coating composition is also disclosed. A method of detecting an article at least partially coated with the coating composition is also disclosed.

A coating composition includes: (i) a film-forming resin; (ii) an infrared reflective pigment; and (iii) an infrared fluorescent pigment or dye different from the infrared reflective pigment. A multi-layer coating including the coating composition, and a substrate at least partially coated with the coating composition is also disclosed. A method of detecting an article at least partially coated with the coating composition is also disclosed.

The present invention provides a glitter pigment, including: a glass flake; a titanium oxide layer formed over the glass flake; and fine gold particles deposited on the titanium oxide layer, wherein the fine gold particles include fine gold particles P2 having a particle diameter of 20 nm or more and less than 50 nm, and in a square region 2 μm on a side on a surface of the titanium oxide layer on which the fine gold particles are deposited, the number of the fine gold particles P2 is 9 or more and less than 100 and an average of distances between the fine gold particles P2 is 130 nm or more and less than 500 nm, each of the distances being a distance from one of the fine gold particles P2 to another fine gold particle P2 nearest to the one.