Process for the production of guanidine derivatives
CA 2091333 C · Owner: Waditschatka, Rudolf · Inventors: Waditschatka, Rudolf
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A process for the production of phenylguanidine carbonate and hydrogencarbonate by, reacting aqueous cyanamide with aniline hydrochloride within a specified pH range, combining the reaction mixture with an alkali metal carbonate or hydrogencarbonate, and, separating the crystalline product.
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 March 9, 1993 and granted August 19, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 9, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 9, 2015.
- 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.