MANUFACTURING METHOD OF BLUE PHOSPHOR MATERIALS FOR EL DEVICE

摘要

A method for preparing a blue inorganic phosphor powder for an electroluminescent device is provided to improve the brightness and efficiency of phosphor and to reduce the first sintering time. A method for preparing a blue inorganic phosphor powder comprises the steps of solubilizing a flux and an activator salt and mixing it with ZnS and sulfur; firstly sintering it in air for a certain time; washing it with distilled water, a HCl aqueous solution, a CH3COOH aqueous solution and a KCN aqueous solution in turn to remove the material remaining after the reaction; adding an activator salt and a sensitizer to it and milling it to obtain a cubic particle; adding sulfur to it to compensate the sulfur lost in the first sintering process; secondly sintering it in air for a certain time; pulling it to air directly to reduce the cooling time and to improve brightness by rapid cooling; secondly washing it by using the same method above; sieving the dried powder by size; and coating the powder by sol-gel method to form a SiO2 protective film on a ZnS-based phosphor powder.