Magnetic recording media

US5266407A · kind A · utility

Assignee

• BASF Magnetics GmbH · DE

Inventors

• Uwe Keppeler · Hochdorf-Assenheim, DE
• Michael Bobrich · Haßloch, DE
• Helmut Auweter · Schifferstadt, DE
• Rudolf Suettinger · Heidelberg, DE
• Albert Kohl · Laumersheim, DE
• Hermann Dikow · Hockenheim, DE
• Werner Lenz · Bad Dürkheim, DE
• Gregor Brodt · Heppenheim, DE

Key dates

• Filing date: Dec 11, 1991
• Grant date: Nov 30, 1993
• Expiry date: Dec 11, 2011

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T428/31609
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

In magnetic recording media consisting of a nonmagnetic substrate and one or more magnetizable layers bonded thereon and based on a polyurethane binder, the binder consists of not less than 50% by weight of an isocyanate-free, branched polyurethane which is soluble in tetrahydrofuran and has sulfonate groups along the polyurethane branches and OH-containing urea groups at the chain ends and a molecular weight of from 4,000 to 30,000.