Hydrophilic copolymer and a method for its production
CA 1293586 C · Owner: Wichterle, Otto · Inventors: Michalek, Jiri; Vodnansky, Jiri; Wichterle, Otto
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A hydrophilic copolymer can be prepared by the copolymerization of a monomer mixture of 2-hydroxyethyl methacrylate and 2-(2-hydroxyethoxy)ethyl methacrylate in, an amount ranging from 90 to 99.99 wt.% with free, methacrylic acid or acrylic acid or with at least one of their sodium, potassium or ammonium salts in an amount ranging from 10 to 0.01 wt.% in the presence of radical initiators. The content of 2-(2-hydroxyethoxy)ethyl methacrylate in the monomer mixture of 2-hydroxyethyl methacrylate and 2-(2-hydroxyethoxy)ethyl methacrylate ranges from 0 to 50 wt.% and the entire monomer mixture contains from 0.01 to 4 wt.% of a crosslinking agent having at least two olefinic double bonds. The …
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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
- Granted December 24, 1991. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended December 24, 2008.
- 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.