Automatic transmission fluid composition
US6110879A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 15, 1998 |
| Grant date | Aug 29, 2000 |
| Priority date | — |
| Expiry date | Oct 15, 2018 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC10N2040/046
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
The present invention provides for a lubricating composition including: a hydrocracker-derived, highly naphthenic, low viscosity index mineral oil; from about 2 wt. % to about 14 wt. % of at least one polymethacrylate polymer; and from about 2 wt. % to about 14 wt. % of a performance additive package. The hydrocracker-derived, highly naphthenic, low viscosity index mineral oil is prepared by: (1) passing a first bottoms portion including not more than about 67 wt. % of a fuels hydrocracker bottoms recycle stream to a dewaxing zone; and (2) passing a second bottoms portion including at least about 33 wt. % of the recycle stream back to the fuels hydrocracker for additional processing; and where the recycle stream has a viscosity at 100.degree. C. of less than about 4.0; (3) contacting the first bottoms portion with a dewaxing catalyst under catalytic dewaxing conditions, where at least a portion of the hydrocracker bottoms is substantially dewaxed; and (4) contacting at least a portion of the substantially dewaxed hydrocracker bottoms with a hydrofinishing catalyst under hydrofinishing conditions, thereby producing a hydrofinished, dewaxed hydrocracker bottoms; and removing from the…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.