Process for alkylating elemental phosphorus
CA 2311950 A1 · Owner: Kolbe, Gunter · Inventors: Weferling, Norbert; Kolbe, Gunter; Stelzer, Othmar
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The invention relates to a method for producing alkali and/or alkaline-earth salts of alkylphosphonous acids and dialkylphosphinic acids from elemental yellow phosphor and alkyl halides, characterised in that the reaction takes place in the presence of aqueous alkali or alkaline-earth hydroxide or mixtures thereof. The invention also relates to the use of the compounds obtained according to the inventive method for producing flameproofing agents extracting agents and plant protection agents.
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 November 17, 1998. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended November 17, 2018.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 17, 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.