Oleaginous compositions containing novel ethylene alpha-olefin polymer viscosity index improver additive
CA 2034716 C · Owner: Exxonmobil Chemical Patents Inc. · Inventors: Struglinski, Mark Joseph
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The present invention is directed to a lubricating oil composition exhibiting improved viscosity index comprising lubricating oil and a viscosity improving effective amount of ethylene alpha-olefin polymer comprising monomer units derived from ethylene and at least one alphaolefin represented by the formula H2C = CHR1 wherein R1 is an alkyl group of from 1 to l8 carbon atoms and wherein, said polymer has a number average molecular weight of from above 20,000 to about 500,000, and an average of at least about 30% of the polymer chains contain terminal ethylidene unsaturation.
Read the whole patent
Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed January 22, 1991 and granted December 25, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended January 22, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by January 22, 2013.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.