Process for producing lithium-containing ferrimagnetic materials

Abstract

The invention is a process for manufacturing a material, a mass of finely divided particles of which an applied magnetic field can induce to change from a non-magnetized condition, in a sense of exhibiting no net external field, to a magnetized condition, in a sense of exhibiting an external field, which comprises: A. reacting starting materials comprising a salt of an alkali metal, e.g., lithium, sodium or potassium, a salt of a first metal in a divalent state, a salt of iron in a trivalent state, at least one of said salts being a halide, and an epoxy compound in the presence of a solvent selected from the group consisting of lower alkanols and water to obtain a mixture comprising a metal hydroxide-containing and solvent-containing gel; B. drying said gel to remove the majority of the solvent therefrom without significantly altering the distribution of lithium, sodium, or potassium therein to obtain porous particles; and C. heating the porous particles to produce the desired material. The preferred starting materials comprise a salt of lithium, a salt of manganese or magnesium, a salt of iron and propylene oxide, the preferred salts being the halides and, more particularly, the chlorides. The preferred solvent is methanol. Freeze drying is the preferred drying method.

Dependencies are inferred from the claim text.