| 摘要 |
PROBLEM TO BE SOLVED: To provide a low-noise magnetic recording medium having superior high-density recording characteristics and a magnetic coating material to be used, when the magnetic recording medium is manufactured. SOLUTION: This magnetic recording medium has a nonmagnetic support 102 and a magnetic layer 103 formed, by kneading the pretreated ferromagnetic powder together with at least an organic solvent and a binder, to obtain the ferromagnetic powder-dispersed magnetic coating material and applying the obtained magnetic coating material on the support 102. The pretreatment of the ferromagnetic powder is carried out, by immersing ferromagnetic powder in a strong acid to dissolve the surface, rinsing the surface-dissolved ferromagnetic powder with water until metallic ions do not exist on the surface, neutralizing the ferromagnetic powder, adding an auxiliary dispersant (suitably a water-soluble silane compound) to the neutralized ferromagnetic powder without drying it and extracting the auxiliary dispersant-added ferromagnetic powder.
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