Device for the magnetic orientation of magnetic recording media

US4003336A · kind A · utility

Assignee

• BASF SE

Inventors

• Eberhard Koester · Bischofswerda, DE
• Paul Deigner · Bad Dürkheim, DE
• Roland Falk · Achern, DE
• Karl Uhl
• Dieter Schaefer

Key dates

• Filing date: Aug 13, 1975
• Grant date: Jan 18, 1977
• Expiry date: Aug 13, 1995

Classification

• Technology area (CPC G): Physics
• CPC primary: G11B5/845
• WIPO field: Audio-visual technology
• WIPO sector: Electrical engineering

Abstract

A device for manufacturing magnetic recording media in which the magnetic particles in the recording layer are oriented in a preferred direction, the fluid coating applied to the base being subjected to the action of a magnetic field produced in the air gaps between the spaced apart poles of two magnetic circuits, one on each side of the coated face, arranged symmetrically with respect to the plane of the coated base, the edges of the poles adjacent to the coated base terminating in screening elements shaped in such a way that the distance between the surfaces of the screening elements facing the coated base and the coated base itself increases as the screening elements extend away from the edges of the poles. A high degree of magnetic anisotropy in the recording layer can also be obtained when the magnetic circuits are at a relatively large distance from the still fluid magnetic coating.