Viscosity modification of mineral oils
CA 2016994 C · Owner: Van Der Linden-Lemmers, Wilhelmina J.M. · Inventors: Van Der Linden-Lemmers, Wilhelmina J.M.; Reynhout, Marinus J.; Schadenberg, Hendrik
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Mineral oil composition comprising an additive which has been prepared by copolymerizing a mixture of at least two alpha-olefins with at least 16 carbon atoms each in the presence of a catalyst comprising a) a tetravalent titanium compound on a magnesium dihalide support and an alkyl ester of an aromatic carboxylic acid and b) a trialkyl aluminium compound.
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 May 17, 1990 and granted July 10, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended May 17, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 17, 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.