Abstract: A magnetic recording medium having a non-magnetic support and a magnetic layer formed thereon, wherein the magnetic layer comprises a ferromagnetic powder, a binder and a non-magnetic inorganic powder, and wherein at least 95% of the non-magnetic powder particles contained in the magnetic layer have a particle size of 0.05 to 0.013 ?m, provide that the non-magnetic powder particles are those found in a field of view of 1.8 ?m×2.4 ?m when the surface of the magnetic layer is observed with a scanning electron microscope at a magnification of 50,000 times.

Abstract: Provided is a magnetic recording medium affording good head contact and high output in addition to excellent head abrasion characteristics acceptable to high data transmission rates. The magnetic recording medium comprises a nonmagnetic layer comprising a nonmagnetic powder and a binder and a magnetic layer comprising a ferromagnetic powder and a binder in this order on a support. Said magnetic layer comprises an abrasive in a quantity of 2 to 5 weight percent with respect to the ferromagnetic powder, the number of protrusions having a height of 3 to 7 nm per 23,000 ?m2 of a surface of the magnetic layer, measured by a non-contact three-dimensional structure analyzing microscope, ranges from 50 to 200, and said magnetic layer has a microindentation hardness ranging from 40 to 80 kg/mm2 at a load of 6 mgf.

Abstract: A magnetic recording medium having on a nonmagnetic support at least one magnetic layer that contains a ferromagnetic metal powder and a binder and has surface roughness of 3 nm or below, with that the ferromagnetic metal powder has an average major-axis length of 30 to 100 nm and saturation magnetization ?s of 70 to 100 A·m2/kg and the magnetic layer further contains SiO2 grains having an average size of 5 to 30 nm, which shows excellent electromagnetic conversion characteristics, ensures reduction in MR head abrasion and has enhanced scratch resistance.

Abstract: A magnetic recording medium which includes a non-magnetic substrate having a front side and a backside, a longitudinal direction and a crossweb direction, with a particulate/binder magnetic layer formed over the front side of the substrate, wherein the magnetic medium has a cross web dimensional difference from the magnetic recording head used therewith of less than 900 microns/meter over a 35 degree temperature range, and over a 70% relative humidity range. In one embodiment, the substrate is a polymeric film which has been subjected to a biaxial tensilization process, thus having a lower coefficient of hygroscopic expansion and coefficient of thermal expansion than an otherwise identical film substrate which has not been biaxially tensilized. The magnetic recording medium formed using such a tensilized substrate has a Wyko Ra smoothness of less than about 10 nm, and a coefficient of thermal expansion from about 5 ppm/C to about 10 ppm/C.