| 摘要 |
PURPOSE:To obtain a magnetic recording medium which can realize high-density recording and has excellent corrosion resistance and dispersibility by incorporating specific iron-aluminum magnetic powder and carbon black into a magnetic layer. CONSTITUTION:The iron-aluminum magnetic powder and the carbon black are incorporated into the magnetic layer. The Fe-Al magnetic powder in which the content of Al is specified to 0.5wt.%-20% with respect to Fe is used as the magnetic powder in this case. The magnetic powder, therefore, exhibits the high corrosion resistance intrinsic to the Fe-Al powder and has good dispersibility. The corrosion resistance and dispersibility are extremely poor if the content of Al is below 0.5% and the electromagnetic conversion characteristic is deteriorated if the content exceeds 20%. Since the carbon black is specified in BET value to >=15m<2>/g and <80m<2>/g, the coefft. of friction thereof is lowered and the light shielding property is improved. In addition, the oil absorption thereof is specified in DBP value to 110-200ml/100g and, therefore, dispersibility is satisfactory maintained. |
