Two-stroke engine oils
CA 2117446 C · Owner: O&D Trading Limited · Inventors: Fotheringham, John D.; Mcmahon, John
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
This invention relates to a two-stroke engine oil which comprises polybutene base oils which are either very low in or are substantially free of n-butenes in the polymer backbone. The absence of n-butenes in the polybutenes significantly reduces smoke emission in exhaust gases generated by the use of the engine oil. Polybutenes such as ULTRAVIS~ which are substantially free of chlorine and have a high degree of terminal unsaturation are particularly preferred.
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 August 10, 1994 and granted November 4, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended August 10, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 10, 2016.
- 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.