| 摘要 |
PURPOSE:To simply obtain fine Ba-ferrite powder having uniform crystal form and suitable for magnetic recording or other use by heating an alkaline aqueous soln. contg. ions of elements in a ratio required to form Ba-ferrite and calcining the resulting precipitate. CONSTITUTION:An aqueous soln. is prepared having >=12 pH and contg. ions of elements in a ratio required to form Ba-ferrite represented by the formula (where M is Co, Ti, Mn, Cu, Zn, In. Ge or Nb; m is 0-0.2; and n is 5.4-6). By holding the soln. at 150-250 deg.C for about 20min-2hr in an autoclave or the like, a precursor of the Ba-ferrite is precipitated. This precipitate is washed, dried and calcined by holding at >=800 deg.C for about 1hr to obtain microcrystalline Ba-ferrite having about 0.05-0.5mum particle size in the lateral direction and perfect hexagonal platelike crystal form. |
