Stock material or miscellaneous articles – Web or sheet containing structurally defined element or... – Physical dimension specified
Patent
1981-08-12
1984-10-16
Robinson, Ellis P.
Stock material or miscellaneous articles
Web or sheet containing structurally defined element or...
Physical dimension specified
428208, 428209, 428411, 428522, 428694, 428693, 428900, 427131, 427128, 360134, 360135, 360136, 252 6254, G11B 572
Patent
active
044775202
DESCRIPTION:
BRIEF SUMMARY
BACKGROUND OF THE INVENTION
The present invention relates to magnetic recording media, particularly magnetic recording media having a lubricated contact layer for the purpose of improving wear characteristics.
THE PRIOR ART
Magnetic recording media are used in various forms, e.g., discs, tapes, drums and cards. Generally, such magnetic recording media comprise a permanent substrate and a magnetic recording layer formed on at least one side of the substrate. A substrate may be a disc of metal, e.g., aluminum or a film of plastic, e.g., linear polyester. A magnetic recording layer may be a magnetically continuous film which is formed of a ferromagnetic material sputtered or plated on the substrate or a magnetically discontinuous film obtained by coating the substrate with a so-called magnetic paint, drying and, then, curing the paint film. In such a magnetically discontinuous film ferromagnetic particles such as iron oxide are dispersed in a binder, such as a polymer material.
Among the ferromagnetic materials, .gamma.-Fe.sub.2 O.sub.3 is most frequently used. However, other material, such as Co-.gamma.-Fe.sub.2 O.sub.3, CrO.sub.2, Fe or Fe--Co may be used. The binder polymer material may be a thermosetting resin, e.g., an acrylic, an epoxy, a phenolic or a melamine resin or a thermoplastic resin, e.g., a polyvinyl buthyral or a polyvinyl acetate resin.
These magnetic recording media are utilized in conjunction with magnetic recording heads or transducers to produce the desired reading or writing properties. In order to obtain a higher recording density, it is necessary for the magnetic recording layer to be thinner and/or for the magnetic head to float over the magnetic recording layer with a narrower gap therebetween. However, a thin magnetic recording layer reduces its mechanical strength and a narrow gap between the magnetic head and the recording layer increases the probability of their contact. Once the heads clash against the surface of the magnetic recording media the magnetic recording layers are apt to be damaged, and, thereby, the recorded information will be destroyed.
Recently, a monolithic head was developed by consolidating a magnetic core and a slider in order to decrease the floating height, i.e., the above-mentioned gap. However, this monolithic head has to suffer from sliding contact with the magnetic recording layer at the time of start and stop. This loading method is called "Contact Start and Stop" method. When the magnetic recording disc stands still, the monolithic head rests on the disc. As the disc begins to rotate, the head gradually floats up aerodynamically over the disc. Thus, the head contacts with the surface of the rotating disc, before the disc obtains certain rotations per minute, where an aerodynamic force necessary for floating up is effected. Again, the head and the disc contact each other, as the disc begins to cease its rotation.
Therefore, the head and the disc cannot avoid frictional resistance at the start and stop of their operation. Consequently, the magnetic recording layer easily wears because of the frictional resistance, unless the contact layer thereof sufficiently can be lubricated.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide magnetic recording media having a wear-resistant magnetic recording layer.
It is another object of the present invention to provide durable magnetic recording media.
It is still another object of the present invention to provide a magnetic disc which can be used in the so-called "Contact Start and Stop" method.
Other objects and advantages of the present invention will further become apparent from the following description of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
According to the present invention, there are provided magnetic recording media comprising a permanent substrate and a magnetic recording layer formed on at least one side of said substrate, said magnetic recording layer comprising a contact layer of a polymer material which contains polyvinyl alkyl et
REFERENCES:
patent: 3523086 (1970-08-01), Bisschops et al.
patent: 3778308 (1973-12-01), Roller et al.
patent: 4046932 (1977-09-01), Hartmann
patent: 4267238 (1981-05-01), Chernega
patent: 4309482 (1982-01-01), Suzuki et al.
patent: 4327139 (1982-04-01), Schaefer
patent: 4390601 (1983-06-01), Ono
Hamada Mitsuru
Ishida Shoji
Kumai Toshio
Fujitsu Limited
Robinson Ellis P.
LandOfFree
Magnetic recording media having lubricated contact layer does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Magnetic recording media having lubricated contact layer, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Magnetic recording media having lubricated contact layer will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1945455