Expired Canadian patentCanada
Ester-free ethers
CA 2115745 C · Owner: Exxonmobil Chemical Patents, Inc. · Inventors: Mathys, Georges M. K.; Godwin, Allen D.
Overview
Drawings and full text
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Ethers, for example those produced by acid-catalysed dehydration of alcohols are freed from esters by treatment with an alkoxide, and are especially suitable as drilling fluid components.
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 14, 1992 and granted December 10, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended August 14, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 14, 2014.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
FiledAugust 14, 1992
GrantedDecember 10, 2002
Term endedAugust 14, 2012
Patent numberCA 2115745 C
Classification (IPC)C07C43/04 +2 more
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.