Abstract
A new process for manufacturing magnetic γ-Fe_2O_3 has been established in commercial scale. This process consists of following two steps. The first step is preparation of acicular α-Fe_O_3 particles by hydrothermal reaction with crystal control agents from amorphous Fe(OH)_3, and the second step is conversion to γ-Fe_2O_3 by calcination using those α-Fe_2O_3 for precusor instead conventional acicular FeOOH. The γFe_2O_3 from this process has good magnetic properties and excellent electoro-acoustic properties on magnetic tapes due to good particle shape and non-pore the particles. The outline of this process and properties on products are described.
