Low volatility lubricating compositions
US5789355A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 20, 1996 |
| Grant date | Aug 4, 1998 |
| Priority date | — |
| Expiry date | Dec 20, 2016 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC10N2070/02
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
This invention relates to low volatility 5W20, 5W30, 10W40, 10W50, 15W40 or 15W50 multigrade oils for crankcase lubrication of gasoline and diesel engines, the oils comprising: PA1 a) basestock having an average basestock neutral number of not less than 105 for a 5W multigrade, not less than 145 for a 10W multigrade and not less than 200 for a 15W multigrade, PA1 b) a detergent inhibitor package including an ashless dispersant comprising an oil soluble polymeric hydrocarbon backbone having functional groups in which the hydrocarbon backbone is derived from an ethylene alpha-olefin (EAO) copolymer or alpha-olefin homo- or copolymer having an M.sub.n of from 500 to 7000, and preferably having >30% of terminal vinylidene unsaturation, and PA1 c) a viscosity modifier. These multigrade crankcase oils provide better volatility with reduced use or even without the need for expensive light neutral basestocks or non-conventional lubricant basestocks, while at the same time providing adequate control of sludge and varnish.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.