Process for producing lithium-containing ferrimagnetic materials
US4062920A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 4, 1973 |
| Grant date | Dec 13, 1977 |
| Priority date | — |
| Expiry date | Sep 4, 1993 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01P2006/16
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
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: PA1 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; PA1 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 PA1 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 particu…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.