Process for the manufacture of lubricating base oils
CA 2017634 C · Owner: Shell Internationale Research Maatschappij B.V. · Inventors: Bertaux, Jean-Marie A.; Holley, Jean-Claude M.; Janssen, Martinus M. P.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Lubricating base oils having a high viscosity index, preferably at least 135, are manufactured by catalytic hydroisomerisation of a hydrocarbonaceous feedstock, derived from a waxy crude oil which, feedstock has not been treated to remove a lubricating base oil fraction and which feedstock contains at least 30% by weight wax and has at least 80% by weight boiling above 300 °C and at most 30% by weight boiling above 540 °C.
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 28, 1990 and granted August 14, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended May 28, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 28, 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.