| 摘要 |
PURPOSE:To obtain the flexible recording medium which is suitable for high density recording by substituting Co by a part of Fe in hexagonal crystal ferrite which contains a specified element A and is expressed by AFe12O10, and employing fine magnetic particles whose C axis is vertical to the plane. CONSTITUTION:As the magnetic powder forming a magnetic recording layer, is employed the particles of Co substituted hexagonal crystal ferrite or Co substituted hexagonal crystal ferrite which is substituted by other ions for compensating the number of valancy. For example, a specified element A is Ba, Sr, Ca, or Pb; and M is V, Nb, Sb, or Ta; and X=0.5-1.1: Then, we obtain AFe12-xCoxO10-xFex, AFe12-3/2xCoxM1/2xO10, and the like. If x<0.5, the vertical magnetization is not sufficient. If x>1.1, the magnetic recording is difficult. If the diameter of the fine particles of ferrite is less than 0.01mu, ferromagnetism is not expressed; and if it is more than 0.3mu, the high-density vertical magnetization cannot be implemented. The 10-40pts.wt. of phenol resin and the like, 0.5-20pts.wt. fatty acid, and 200pts.wt. of solvent are added to 100pts.wt. of the fine particles. Then, they are blended, rolled, dried; and the work is finished. |
