Method for reducing foaming of lubricating oils
US6090758A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 7, 1997 |
| Grant date | Jul 18, 2000 |
| Priority date | — |
| Expiry date | Jan 7, 2017 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC10N2040/28
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
Foaming of a lube oil comprising a base stock derived from wax isomeration and an additive package is effectively reduced to within specification limits of 50 ml/ml over a temperature range of from at least 24.degree. C. to 93.5.degree. C. by adding to the oil an effective amount of an antifoamant exhibiting a spreading coefficient of at least about 2 mN/m. This has been found to be particularly effective in reducing foaming of lube oils containing a mixture of a wax isomerate oil and a petroleum oil fraction. Antifoamants typically used with conventional lube oils containing one or more petroleum fraction base stocks, but which do not exhibit a spreading coefficient of at least 2 mN/m with the wax isomerate containing oil, have been found not to be effective in reducing the foaming of the oil.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.