| abstract |
Provided is a phosphor material for a white LED with a blue LED or ultraviolet LED as a light source. n A phosphor comprises an α-sialon represented by the formula: (M1) X (M2) Y (Si) 12−(m+n) (Al) m+n (O) n (N) 16−n where M1 is at least one element selected from the group consisting of Li, Mg, Ca, Y and lanthanide metals (except for La and Ce), M2 is at least one element selected from Ce, Pr, Eu, Tb, Yb and Er, 0.3≦X+Y≦1.5, 0<Y≦0.7, 0.6≦m≦3.0, 0≦n≦1.5 and X+Y=m/2; and the oxygen content in a powder of the α-sialon is at most 0.4 mass % larger than a value calculated based on the formula. |