A POWDER COMPRISING BLUE LIGHT-EMITTING PHOSPHOR PARTICLES AND PREPARATION THEREOF

摘要

A powder comprising blue light-emitting phosphor particles is provided to improve electroluminescent strength to a vacuum ultraviolet ray of the wavelength 172 nm corresponding to a Xe2 molecular ray emitted from Xe gas. A powder comprises blue light-emitting phosphor particles having a diopside crystal structure represented by the formula of CaMgSi2O6 : Eu. The Eu element on the particle surface is a mixture containing Eu^(2+) and Eu^(3+) in a ratio ranging from 12 : 88 to 35 : 65 under a condition in which the Eu^(2+) is present on the surface in an amount of 0.020 atom% or more, wherein the atom% means a percentage of the number of the Eu^(2+) present on the surface per the total number of Ca, Mg, Si, O, Eu^(2+), and Eu^(3+) present on the surface.