METHOD FOR MANUFACTURING A SPHERICAL PHOSPHORESCENT MATERIAL AND PLASMA TORCH

摘要

PROBLEM TO BE SOLVED: To provide a manufacturing method capable of obtaining a high-luminance spherical phosphorescent material imparting an excellent afterglow.;SOLUTION: After an electromagnetic valve 12 has been opened, air within a cooling chamber is removed by a vacuum pump, and an electromagnetic valve 13 is opened so as to dispense an inert gas into the cooling chamber. As the pressure of the cooling chamber 11 waxes, an electromagnetic valve 14 is opened so as to commence the external discharge of the inert gas. Next, a gas for generating a plasma is dispensed, and a voltage is impressed in-between a ring-shaped cathode 4 and an anode 3, and as a result, a plasma jet flame P is generated. In a case where phosphorescent particles are subsequently inputted from above, the inputted phosphorescent particles are melted while being mobilized without deviating from the center of the plasma abiding in a maximal temperature state and then fall into the cooling chamber 11. The particles melted by the ultra-high-temperature heat at the center of the plasma are rapidly cooled within the cooling chamber 11 and then accumulated, as spherical particles 15, on the bottom of the cooling chamber 11. Upon the completion of the plasma melting treatment, the bottom plate 16 of the cooling chamber is opened, and after the spherically reshaped phosphorescent particles 15 have been retrieved, the operation is concluded.;COPYRIGHT: (C)2014,JPO&INPIT