Superparamagnetic solid particles

US4810401A · kind A · utility

Assignee

• BASF SE

Inventors

• Gunther Mair · Mannheim, DE
• Werner Steck · Ludwigshafen, DE

Key dates

• Filing date: May 28, 1987
• Grant date: Mar 7, 1989
• Expiry date: May 28, 2007

Classification

• Technology area (CPC A): Human Necessities
• CPC primary: A61K49/1842
• WIPO field: Pharmaceuticals
• WIPO sector: Chemistry

Abstract

Superparamagnetic solid particles of the general formula I EQU M.sub.v Mn.sub.w Zn.sub.x Fe.sub.y O.sub.z (I) where M is Co and/or Ni, v and w are each from 0 to 0.998, x is from 0.001 to 0.998, y is from 2.001 to 2.998, z is from 3.001 to 4, v+w+x is from 0.002 to 0.999, v+w+x+y is 3, v.noteq.0 if w=0 and w.noteq.0 or v=0, polar and nonpolar superparamagnetic liquids which contain the surfactant-coated superparamagnetic solid particles I in the form of a colloidal dispersion in polar or nonpolar liquid media, and processes for the preparation of polar and nonpolar superparamagnetic liquids.