Low molecular weight water soluble phosphinate and phosphonate containing polymers
CA 2018772 C · Owner: Rohm And Haas Company · Inventors: Swift, Graham; Hughes, Kathleen A.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Described herein is a process to efficiently utilize the chain transfer agent hypophosphorous acid or salts in the preparation of low molecular weight polycarboxylate polymers comprising employing in process neutralization of the carboxylic acid monomers. Also described is a low molecular weight polycarboxylate polymer containing phosphinate and phosphonate functional groups where less than 20% of the phosphorus is present in inorganic non polymeric compounds.
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 June 12, 1990 and granted June 12, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended June 12, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 12, 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.