Preparation of Nano-Size Magnetic Gamma Ferric Oxide ( γ-Fe 2 O 3 ) and Magnetite ( Fe 3 O 4 ) Particles for Toner and Color Imaging Applications

In the present study, we report a chemical synthesis technique for the preparation of gamma ferric oxide (γ-Fe2O3) and magnetite (Fe3O4) particles in the nanometer size range. The particles are produced in powder form by precipitation in the aqueous cores of water-in-oil microemulsions. The latter act as constrained reactors for the precipitation reaction. X-ray diffraction was used to identify the particles and TEM was used for size determination. The magnetization data demonstrate the superparamagnetic behavior of the particles. To prevent the particles from aggregation, the particles were covered with a monolayer of vinyltriacetoxy silane. The nanosize magnetic particles have potential applications in the manufacture of colored magnetic toners.

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