Patent · US Expired

Manufacture of magnetic discs

US4133911A · kind A · utility

5Cited by

4References

8Claims

0Family size

Assignee

BASF SE

Inventors

Eberhard Koester · Bischofswerda, DE
Paul Deigner · Bad Dürkheim, DE
Roland Falk · Achern, DE
Karl Uhl
Dieter Schaefer
Dieter Mayer · Ludwigshafen, DE
Herbert Motz · Beindersheim, DE
Peter Felleisen · Lampertheim, DE

Key dates

Filing date	Dec 16, 1975
Grant date	Jan 9, 1979
Priority date	—
Expiry date	Dec 16, 1995

Classification

Technology area (CPC G)Physics
CPC primaryG11B5/842
WIPO fieldAudio-visual technology
WIPO sectorElectrical engineering

Abstract

The invention relates to an improved process for the manufacture of magnetic discs carrying very thin magnetic layers, by applying a fluid dispersion of magnetic materials in a binder mixture to rigid base discs by the spin-coating process. Above the side of the base disc which is to be provided with the magnetic layer, there are arranged means which produce an aerodynamic boundary layer above the discs during rotation of the latter. This avoids the formation of surface irregularities and of coating streaks during production of the layer by spin-coating.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.