PURPOSE: To obtain a magnetic recording medium which has good dispersibility of a ferromagnetic material and has high S/N and is suitable for a video, etc. by adjusting the moisture to be adsorbed to a ferromagnetic material having a specific value or above of an SBET specific surface area to a prescribed rate and dispersing the same into a binder.
CONSTITUTION: Magnetic powder which is magnetic iron oxide contg. CO, etc., has ≥35m2/g specific surface area and is subjected to moisture conditioning to ≥0.8wt% and <1.2wt% adsorption moisture is mixed and dispersed together with necessary carbon black and solvent into a binder. An additional amt. of a binder and lubricating agent and, if necessary, a polishing agent, for example, Cr2O3 powder, etc. are mixed and dispersed with such dispersion. The dispersion mixture is coated on a non-magnetic substrate and is dried and cured to form a magnetic layer. The dispersibility of the ferromagnetic material powder into the binder is improved and the bonding force between the magnetic powder and the binder is increased by incorporating suitable water into the ferromagnetic material powder, by which the magnetic recording medium having high S/N and squareness ratio is obtd.
MASUYAMA KENICHI
IDESAWA SHINICHIROU
OKUTSU TOSHIMITSU
NASU KATSUO
AOKI NOBUO
FUJIYAMA MASAAKI
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