High molecular weight polyvinylpyrrolidones and method for their preparation
CA 2079911 A1 · Owner: Isp 3 Corp. · Inventors: Mandella, William L.; Tazi, Mohammed
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An uncrosslinked water-soluble polyvinylpyrrolidone having a K-value in excess of 120 and containing less than about 0.1 percent by weight of residual monomer. A method for preparing the high molecular weight polyvinylpyrrolidone is also disclosed.
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 28, 1991. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended March 28, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 28, 2013.
- 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.