Patent · US Expired

Manufacture of acicular magnetic iron oxide

US4259368A · kind A · utility

10Cited by

4References

4Claims

0Family size

Assignee

BASF SE

Inventors

Peter Rudolf · Ludwigshafen, DE
Werner Steck · Ludwigshafen, DE
Wilhelm Sarnecki · Schifferstadt, DE
Christof Jaeckh · Heidelberg, DE

Key dates

Filing date	Apr 8, 1980
Grant date	Mar 31, 1981
Priority date	—
Expiry date	Apr 8, 2000

Classification

Technology area (CPC G)Physics
CPC primaryG11B5/70657
WIPO fieldAudio-visual technology
WIPO sectorElectrical engineering

Abstract

A process for the manufacture of acicular magnetic iron oxides which consist of a core of gamma-iron(III) oxide and a shell of a magnetite modified with zinc(II) ions and/or manganese(II) ions and which contain, based on the total modified gamma-iron(III) oxide, from 0.1 to 20 percent by weight of iron(II) ions, from 0.1 to 10 percent by weight of zinc(II) ions and/or from 0.1 to 10 percent by weight of manganese(II) ions.

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