Patent · US Expired

Production of magnetic recording media

US4000336A · kind A · utility

2Cited by

5References

10Claims

0Family size

Assignee

Badische Anilin- & Soda-Fabrik Aktiengesellschaft

Inventors

Job-Werner Hartmann · Ludwigshafen, DE
Hans-Joerg Hartmann
Hermann Roller · Ludwigshafen, DE
Joachim Hack · Ludwigshafen, DE
Heinrich Hartmann · Schifferstadt, DE

Key dates

Filing date	Nov 6, 1974
Grant date	Dec 28, 1976
Priority date	—
Expiry date	Nov 6, 1994

Classification

Technology area (CPC Y)Emerging Cross-Sectional Technologies
CPC primaryY10S428/90
WIPO fieldAudio-visual technology
WIPO sectorElectrical engineering

Abstract

In a process for the production of magnetic recording media by applying a layer of a dispersion of a magnetic pigment in a polyurethane-containing binder and a solvent to non-magnetic supports, small amounts of ethylenically unsaturated polymerizable carboxylic acids or their anhydrides with or without copolymerizable monomers are added and polymerized during dispersion of the magnetic pigment. Recording media produced by this process exhibit excellent output level, coefficient of friction and electrical resistance values and have particularly good operational durability.

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