| 摘要 |
PROBLEM TO BE SOLVED: To provide a magnetic recording medium having excellent electromagnetic conversion characteristics, such as frequency characteristics, and preservable stability and with which the recording of a higher density is possible. SOLUTION: This medium has a base 2 and a magnetic layer 3 on this base 2 and this magnetic layer 2 contains ferromagnetic metallic powder and a binder. The surface roughness of the magnetic layer 3 is <=10nm, the coercive force thereof is larger than 1500Oe, the squareness ratio thereof is >=0.85 and the residual magnetic flux density thereof is >=2600 gauss. The attenuation factor ΔBs (the change rate of the saturation magnetic flux density Bs' after resting for 30 days under the environment of 60 deg.C and 90% relative humidity to the saturation magnetic flux density Bs of the magnetic layer before the resting and is the value expressed by ΔBs=(1-Bs'/Bs)×100) of the raturation magnetic flux density is <=10%. This process for producing the magnetic recording medium includes a state for forming a coating material for kneading a coating material compsn. prepd. by using the specific ferromagnetic metallic powder and the binder in such a manner that the solid content attains >=70wt.%. |
