Superparamagnetic fluids and methods of making superparamagnetic fluids
US5064550A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 8, 1990 |
| Grant date | Nov 12, 1991 |
| Priority date | — |
| Expiry date | Jun 8, 2010 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01F1/442
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A superparamagnetic fluid having a non-polar hydrocarbon oil carrier liquid and coated magnetic particles coated with at least one acid selected from the group consisting of an organic acid containing only carbon and hydrogen atoms in the chain connected to the carboxyl group, wherein the chain contains at least 19 carbon atoms, and an amino acid acylated with a fatty acid, provided that said organic and amino acids are branched, unsaturated, or both. A method of making a superparamagnetic fluid, including providing an aqueous suspension of coated magnetic particles coated with at least one acid selected from the group consisting of an organic acid containing only carbon and hydrogen atoms in the chain connected to the carboxyl group, wherein the chain contains at least 19 carbon atoms, and an amino acid acylated with a fatty acid, provided that said orgaic and amino acids are branched, unsaturated, or both. The coated magnetic particles are then separated from water in the aqueous suspension and then dispersed in a non-polar hydrocarbon oil carrier liquid to form a superparamagnetic fluid.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.