Lubricating oil compositions and additives for use therein
CA 2010606 C · Owner: Exxon Chemical Patents, Inc. · Inventors: Ritchie, Andrew James Dalziel; Colclough, Terence
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Substituted para-phenylene diamines have been found to be effective antioxidants capable of protecting crankcase lubricating oils from thickening and sludge formation after prolonged exposure to oxygen at elevated temperature.
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 February 21, 1990 and granted December 19, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended February 21, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 21, 2012.
- 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.