| abstract |
An oxynitride phosphor powder containing α-SiAlON and aluminum nitride and having a composition represented by the compositional formula: Ca x1 Eu x2 Si 12-(y+z) Al (y+z) O z N 16-z (wherein x1, x2, y and z are 0<x1≤3.40, 0.05≤x2≤0.20, 4.0≤y≤7.0 and 0≤z≤1). The oxynitride phosphor powder above, wherein the reflectance of light having a peak wavelength of the fluorescence emitted by excitation with light having a wavelength of 450 nm is 80% or more. A crystalline silicon nitride powder for the production of oxynitride phosphor powder, wherein the oxygen content is from 0.2 to 0.9 mass%. A method for producing an oxynitride phosphor powder, comprising a first step of mixing raw material substances and firing the mixture at a temperature of 1,500 to 2,000°C in an inert gas atmosphere to obtain a fired oxynitride represented by the formula above, and a second step of heat-treating the fired oxynitride at a temperature of 1,100 to 1,600°C in an inert gas atmosphere. |