Patent · US Expired

Preparation of magnetic recording media

US4597990A · kind A · utility

3Cited by

2References

5Claims

0Family size

Assignee

BASF SE

Inventors

Hermann Roller · Ludwigshafen, DE
Joachim Hack · Ludwigshafen, DE
Uwe Woweries
August Lehner
Werner Grau · Frankenthal (Pfalz), DE
Peter Nagel · Highlands, US
Roland Falk · Achern, DE

Key dates

Filing date	Aug 27, 1985
Grant date	Jul 1, 1986
Priority date	—
Expiry date	Aug 27, 2005

Classification

Technology area (CPC Y)Emerging Cross-Sectional Technologies
CPC primaryY10T428/31609
WIPO fieldAudio-visual technology
WIPO sectorElectrical engineering

Abstract

A process for the preparation of a magnetic recording medium by dispersing pulverulent magnetic material in a binder mixture which is dissolved in an organic solvent and essentially consists of an elastomeric polyurethane and a high molecular weight hydroxyl-containing polymer, with addition of dispersing assistants and conventional additives, applying a layer of the dispersion, to which a diisocyanate and/or polyisocyanate has first been added, to a base material and the solidifying the layer and crosslinking the binder matrix, wherein the diisocyanate and/or polyisocyanate is added to the dispersion and, before applying the dispersion to the base, from 15 to 55% of the NCO groups present react with the hydroxyl-containing polymer of the binder mixture.

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