Continuous industrial manufacturing process for an aqueous solution of glyoxylic acid
CA 2029650 C · Owner: Societe Francaise Hoechst · Inventors: Alarcon, Jean-Michel; Schouteeten, Alain
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Continuous manufacturing process for an aqueous solution of glyoxylic acid by nitric oxidation of an aqueous solution of glyoxal carried out in the presence of hydrochloric acid in which the oxidation is effected continuously using 0.80 ~ 0.2 mole of nitric acid and 0.70 ~ 0.05 mole of hydrochloric acid per mole of glyoxal in a reaction medium having a concentration by weight comprised between 5 and 6% of hydrochloric acid and higher than 10% of nitric acid.
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 9, 1990 and granted May 9, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended November 9, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 9, 2012.
- 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.