Abstract: A magnetic recording medium comprising a nonmagnetic substrate having applied thereon through a nonmagnetic underlayer a magnetic recording layer composed of a magnetic metal material, in which the nonmagnetic substrate comprises a substrate having a smooth surface with an average surface roughness Ra of not more than 20 Å, a recesses-and protrusions-forming layer having stripe-like protrusions and recesses in the circumferential direction, formed on the substrate, and a reinforcing coat layer having a hardness higher than that of the recesses-and protrusions-forming layer is sandwiched between the substrate and the recesses-and-protrusions-forming layer. The magnetic recording medium is excellent in a characteristic of friction sliding with a flying-type magnetic head, can improve the reproducing output and S/N ratio while the low noise of the magnetic recording medium is kept without change, and prevents easy production of bit errors.

Abstract: In a magnetic recording medium wherein a magnetic recording layer for storing information, a carbon type protective layer for preventing damage of the magnetic recording layer and a lubrication layer are sequentially formed on a non-magnetic substrate, the carbon protective layer has a relatively smaller hydrogen content on the side nearer the lubrication layer than on the side nearer the magnetic recording layer. In a magnetic head slider having an electromagnetic conversion device mounted thereto, a carbon protective layer is laminated on at least a sliding surface side, and a lubrication layer is disposed on the carbon type protective layer.

Abstract: A magnetic recording medium able to cope with low flying height of the magnetic head in a CSS system and having fine surface roughness, wherein (1) a metal layer having columnar protrusions formed by the filming of Ti or the like or (2) a resin layer or glass resin layer having irregularly distributed through-holes are provided on the substrate of a magnetic recording medium to impart roughness (texture).

Abstract: A method for manufacturing small magnetic disks from a nonmagnetic large disk. A nonmagnetic large disk is first prepared, and subjected to at least one step of a manufacturing process necessary for manufacturing a magnetic disk from a nonmagnetic substrate. The manufacturing process may comprise the steps of applying at least one underlayer to the substrate, applying the layer of magnetic material to the underlayer, applying the protective layer to the layer of magnetic material, applying the lubricating layer to the protective layer, carrying out a texture treatment, polishing the underlayer, and burnishing the protective layer, and carrying out a levitation and characteristic test. After at least one of these steps, the large disk is divided into a plurality of the small disks. Accordingly, it is possible to manufacture small magnetic disks, by the use of manufacturing equipment designed to manufacture large magnetic disks.

Abstract: A magnetic recording medium having an excellent resistance to wear and CSS strength and showing a satisfactory lubricant retention, and processes for production thereof. The magnetic recording medium includes a substrate having formed thereon, in sequence, a magnetic recording layer, a protective coating, and a lubricant coating, the protective coating including a plane portion and a plurality of fine projections and recesses formed on the plane portion.

Abstract: A magnetic recording medium having an excellent resistance to wear and CSS strength and showing a satisfactory lubricant retention, and processes for production thereof. The magnetic recording medium includes a substrate having formed thereon, in sequence, a magnetic recording layer, a protective coating, and a lubricant coating, the protective coating including a plane portion and a plurality of fine projections and recesses formed on the plane portion.