Cross-linked polymers with a porous structure
CA 2179775 C · Owner: Chmelir, Miroslav · Inventors: Chmelir, Miroslav
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The invention relates to cross-linked synthetic polymers based on acrylic acid and its derivatives with a high absorbency and improved absorbency rate for water aqueous solutions, and bodily fluids, a process for their production by radical polymerisation in conditions leading to polymers having a porous structure and a particle density depending on the degree of swelling so that the polymer particles can float in water or aqueous fluids and the use of these polymers for the absorption and/or retention of water and the transfer of water and/or an active agent solution to a surrounding medium. The porous structure of the polymer is formed by nitrogen dispersed in it. At least one azo …
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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 December 19, 1994 and granted March 28, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended December 19, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 19, 2016.
- 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.