Abstract: A magnetic recording device includes a substrate, an intermediate layer disposed on the substrate, a magnetic recording layer disposed on the intermediate layer, and a graphene overcoat disposed on the magnetic recording layer. The graphene overcoat includes at least one layer of a graphene monoatomic layer which is a sheet-like monoatomic layer of sp2 bonded carbon atoms. A transition layer is interposed between the graphene overcoat and the magnetic recording layer. The transition layer includes carbon and at least one metal of the magnetic recording layer.

Abstract: A composition of a hydrocarbon in water colloidal dispersion including hydrocarbon particles having a mean softening point exceeding 95° C., a water soluble dispersion agent and water, process and apparatus for the production thereof are disclosed. These dispersions have a median particle size below about 4.5 microns and 90% of the hydrocarbon particles have a size less than about 60 microns. These dispersions are storage stable, stable towards transportation, and can be pumped without destabilizing.

Abstract: This invention relates to a process for forming a lubricant layer of differing thickness on distinct zones of a maonetic disk of a hard disk drive without heating, inert gas plasma and UV-radiation or E-beam exposition. According to the present invention. an overcoat layer with distinct zones of differing thickness is first sputtered on the disk surface by using distinct masks under different sputtering conditions. A lubricant layer is then uniformly coated on the overcoat layer. Since a part of lubricant is bonded to the overcoat to form a bonded lubricant layer and the thickness of the bonded lubricant layer relates to the overcoat layer's property, a free lubricant layer with zoned thickness is consequently formed, which the free lubricant layer consists of the leftover lubricant. The zoned lubricant layer of the invention hence decreases the flying stiction.

Abstract: A magnetic disk having improved tribological characteristics in the data zone of the disk surface while retaining a low sliding stiction in the landing zone is disclosed. It contains the conventional elements of a substrate, a magnetic recording layer, a protective overcoat, and a lubricant layer on the protective overcoat. However, the lubricant layer is UV irradiated under a photo mask to cause a radially inner zone and a radially outer zone. The photo mask is designed so that the radially outer zone of the lubricant layer has a ratio of bonded/unbonded lubricant molecules greater than that in the radially inner zone. The reduced proportion of mobile lubricant molecules in the data zone prevents the lubricant molecules from being collected by the magnetic head. On the other hand, a large proportion of the lubricant molecules in the landing zone remained mobile. This allowed the sliding stiction in the landing zone to stay at the desiredly low value.