Process for preparing linearly-extended polyalkylenepolyamines
CA 2000699 A1 · Owner: Molzahn, David C. · Inventors: Bowman, Robert G.; Hartwell, George E.; Molzahn, David C.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A process for preparing linearly-extended polyalkylenepolyamines, such as linear and branched polyethylenepolyamines, comprising contacting a difunctional aliphatic alcohol, such as monoethanolamine with a, reactant amine, such as ethylenediamine in the presence, of a catalyst containing tungsten oxide essentially free of the metals of Groups VIII, IB, and IIB of the Periodic Table. Included among the linearly-extended polyalkylenepolyamines are alcohol-extended piperazines such as N-(2-hydroxyethyl)piperazine, and amine-extended piperazines, such as N-(2-aminoethyl)piperazine. 34,711-F
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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 October 13, 1989. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended October 13, 2009.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 13, 2011.
- 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.