| 摘要 |
PURPOSE:To improve the sliding characteristic of a magnetic layer, to prevent the baking on a magnetic head, and to improve the abrasion resistance by incorporating a specified organic zinc compd. into a magnetic layer obtained by dispersing ferromagnetic powder in a binder. CONSTITUTION:A ferromagnetic metal (alloy), preferably in the form of acicular particles, or the magnetic powder of oxide such a gamma-Fe2O3 is charged into an organic solvent of dialkyl dithiophosphate of zinc shown by the formula (R is 1-20C alkyl), agistated, mixed, filtered, dried, and then surface-treated to obtain magnetic powder. The magnetic powder is dispersed and dissolved in a soln. of a resinous binder along with an abrasive, a dispersant, etc. to obtain a magnetic coating liquid which is coated on a nonmagnetic supporting body. The coated body is oriented, dried, and calendered to obtain a smoothe surface. The magnetic powder which is not pretreated with organic zinc can be mixed into the soln. of the binder wherein organic zinc dissolved. The sliding property of the magnetic layer can be particularly improved in this way, as the physical properties such as a electromagnetic transducing characteristic, strength, etc. are maintained. The baking on the head is also prevented, and the magnetic recording medium having excellent durability is obtained. |
