Monocarboxylic acid based antifreeze composition for diesel engines
US6676847B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 8, 2001 |
| Grant date | Jan 13, 2004 |
| Priority date | — |
| Expiry date | May 8, 2021 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC09K5/20
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
The present invention relates to a carboxylic acid based antifreeze coolant formulation for heavy duty applications such as for diesel engines which may be used for inhibition and prevention erosion and corrosion of aluminum and the corrosion of other metals exposed to an aqueous liquid in automotive coolant systems. The formulation further inhibits mineral scale. It may be packaged as an ethylene glycol based additive for use in new engines or in a concentrated inhibition package as an additive as for reinhibition of used coolant. The combination of a mixture of ethylene or propylene glycol, a monobasic carboxylic organic acid, azoles, low levels of molybdates, a nitrite salt and/or nitrate salt and/or siloxane stabilized silicate, and combinations thereof, polyvinylpyrrolidone, provide a synergistic protective effect against the cavitation corrosion of aluminum in aqueous liquids reducing the corrosion rate and is effective at relatively low concentrations and varying pH ranges.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.