Provided is a phosphor having superior light-emitting properties. A phosphor composition includes: a nitride phosphor that contains, in a composition thereof, an element M that is at least one selected from the group consisting of rare earth elements except cerium, silicon, nitrogen, and cerium; and an oxyfluoride. In the phosphor composition, a content of the oxyfluoride relative to the phosphor composition is 1.5% by mass or higher and 10% by mass or lower according to an X-ray diffraction reference intensity ratio method.

The invention relates to a security feature for securing value documents, comprising a chemically unstable inorganic feature substance and a stabilizing component that comprises a substance that stabilizes the feature substance, which substance has at least the same solubility in water as the feature substance to be protected and releases ions when said substance is decomposed, which ions conform to the ions of the feature substance at least in part.

The invention relates to a security feature for securing value documents, comprising a chemically unstable inorganic feature substance and a stabilizing component that comprises a substance that stabilizes the feature substance, which substance has at least the same solubility in water as the feature substance to be protected and releases ions when said substance is decomposed, which ions conform to the ions of the feature substance at least in part.

The present invention provides a safe ultraviolet light irradiation device that uses ultraviolet light safe to the human body and has a wide range of microorganism elimination and sterilization effects, and also provides an ultraviolet light emitting element provided with: an electrode substrate having a pair of electrodes; at least one cylindrical or flattened cylindrical glass tube disposed on the electrode substrate so as to face both of the electrodes, the glass tube having both end parts sealed; a xenon gas-containing discharge gas enclosed inside the glass tube and generating an electric discharge due to a voltage applied to the electrodes; and a phosphor layer formed on an inner surface of the glass tube and emitting light when excited by the electric discharge, wherein the glass tube is made of borosilicate glass or quartz glass; and the phosphor layer is made of a phosphate-based fluorescent material and has an emission spectrum having a peak half value width within a wavelength range of 50 nm or less with a peak at a wavelength of 20310 inm on an illuminance basis.

Provided is a phosphor having superior light-emitting properties. A phosphor composition includes: a nitride phosphor that contains, in a composition thereof, an element M that is at least one selected from the group consisting of rare earth elements except cerium, silicon, nitrogen, and cerium; and an oxyfluoride. In the phosphor composition, a content of the oxyfluoride relative to the phosphor composition is 1.5% by mass or higher and 10% by mass or lower according to an X-ray diffraction reference intensity ratio method.