Separating ammonium chloride from n-hydrocarbyl(thio)phosphoric triamide
CA 2278004 A1 · Owner: Cheng, Chi Hung · Inventors: Sulzer, Gerald M.; Cheng, Chi Hung
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A substantially anhydrous mixture which comprises ammonium chloride the , triamide, and ammonia is formed either by adding ammonia to a mixture of the other components or by conducting, in the presence of the ammonia and an organic solvent, a reaction to form the triamide and ammonium chloride as coproducts. In all cases the ammonia is present in a sufficient excess amount relative to the ammonium chloride to form a separate liquid phase in which the ammonium chloride solids dissolve. Such separate liquid phase is separated from the remainder of said mixture.
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 January 21, 1998. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended January 21, 2018.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by January 21, 2020.
- 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.