COMPLEX OXIDE, PHOSPHOR, PHOSPHOR PASTE AND LIGHT-EMITTING DEVICE

摘要

Disclosed is a complex oxide suitable for phosphors, whose luminance upon irradiation with an excitation source hardly changes over time. Also disclosed are a phosphor containing such a complex oxide, a phosphor paste and a light-emitting device. Specifically disclosed is a complex oxide wherein a part of Mg in a compound represented by the formula (1) below is substituted by M<SUP>3</SUP> which is at least one element selected from the group consisting of group 5 elements and group 6 elements, and the molar ratio of M<SUP>3</SUP> to the total of Mg and M<SUP>3</SUP>, namely M<SUP>3</SUP>/(Mg + M<SUP>3</SUP>), is not less than 0.003 but not more than 0.006. 3M<SUP>1</SUP>O aMgO bM<SUP>2</SUP>O<SUB>2</SUB> (1) (In the formula, M<SUP>1</SUP> represents at least one element selected from the group consisting of Ba, Sr and Ca; M<SUP>2</SUP> represents at least one element selected from the group consisting of Si and Ge; and 0.003 = x = 0.006, 0.9 = a = 1.1 and 1.8 = b = 2.2.)