Method to improve the stability of dispersions of carbon
US6623787B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 26, 2001 |
| Grant date | Sep 23, 2003 |
| Priority date | — |
| Expiry date | Aug 26, 2021 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01P2006/40
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
A method for preventing a carbon dispersion from increasing in viscosity during use is described. The dispersion comprises graphite particles or carbon black particles or a combination of both dispersed in a fluid. The method involves lowering the susceptibility of the carbon dispersion to an increase in viscosity or ionic strength by lowering its pH or reducing its exposure to reactive components in the ambient atmospheric gas. The pH can be lowered by at least partially removing ammonia from the dispersion, or by adding a material that reduces the pH of the dispersion. The stability of the dispersion can also be improved by isolating the dispersion from reactive atmospheric gas. The stabilized aqueous carbon dispersion can have a viscosity of less than about 20 cps and a conductivity of less than about 3 mS.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.