Method for preparing polyesters having intrachain free acid functions
CA 2437520 C · Owner: Ipsen Pharma S.A.S · Inventors: Cazaux, Jean-Bernard; Brigati, Charles; Louchkoff, Alexandre
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 preparing polyesters A containing several mid-chain free acid functions by ring-opening polymerisation in the presence of a chain initiator: the benzyl diester of the tartaric acid the phenyl radical of which is optionally substituted. A: aliphatic based on cyclic esters such as lactides and glycolides.
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 February 22, 2002 and granted August 30, 2011. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended February 22, 2022.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 22, 2024.
- 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.