| 摘要 |
PROBLEM TO BE SOLVED: To obtain an adequate degree of alignment, to lower a perpendicular magnetization component and to improve S/N and electromagnetic conversion characteristics by applying magnetic lines of force in a transporting direction of a base on this base while a coating liquid contg. magnetic powder applied on the base is not yet dry to longitudinally align the coating liquid, then applying AC magnetic fields thereon to randomly align the magnetic powder. SOLUTION: The coating liquid contg. the ferromagnetic metallic powder having Hc of 1,400 to 3,500 Oe and an average major axis diameter of 0.01 to 0.18μm is applied on the continuously moving belt-like base. The base in which the coating liquid is not yet dry is held by opposing permanent magnets of the same pole, by which the magnetic lines of force with which the magnetic field intensity at the gap center is 1/2 to 10 times the coercive force of the magnetic layer are applied in the transporting direction of the base. The magnetic particles of the ferromagnetic metallic powder are magnetically and longitudinally aligned in the specified direction within the magnetic layer surface and are thereafter subjected to the random alignment treatment to magnetically align the particles in all directions. As a result, the magnetic disk which is made smaller in noise, is improved in various characteristics and modulation and has the large capacity optimum for digital recording is obtd.
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