| 摘要 |
PROBLEM TO BE SOLVED: To obtain a phosphor compsn. which can be stored as a dry substance in a loosened state and exhibits a high luminescent efficiency by applying a coating contg. a hydroxycarboxylic acid to a sulfide-contg. phosphor. SOLUTION: This compsn. comprises a sulfide-contg. phosphor with a coating contg. a hydroxycarboxylic acid. The acid is pref. anα-hydroxycarboxylic acid, still pref. citric or tartaric acid. The phosphor is pref. an oxysulfide phosphor. The coating is applied by suspending the phosphor powder in water, adjusting the suspension to weakly acidic or alkaline, adding the hydroxycarboxylic acid in an amt. of 0.001-10wt.%, pref. 0.1-3wt.%, of the phosphor to the suspension, grinding the phosphor in the suspension to a completely loosened state, and separating and drying the phosphor. |
