STUDY ON FABRICATION OF THE MAGNETITE FOR LASER PRINTER

摘要

The paper shows the synthesis of magnetite through application of sodium hydroxide solution to ferrous sulphate solution, and then oxidation by blowing of air, while a consideration is made on variation of shape and size of particles and its magnetic properties according to synthesis condition. The synthesis is conducted at two stages, that is, first reaction to vary alkali ratio from 0.75 to 1.00, and second reaction to eliminate non reactant in such a way as more adding sodium hydroxide.The magnetite available to the magnetic toner for laser printer consists of particles with spherical shape and has specific saturation magnetization of σ_s=90emu/g and coercivity of Hc=45 Oe in properties.