Treatment of contact lenses with an aqueous solution including sulfobetaine compounds
CA 2245174 C · Owner: Heiler, David J. · Inventors: Groemminger, Suzanne F.; Heiler, David J.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The present invention provides methods for treating contact lenses and compositions for the same. The present invention includes contacting a lens with an aqueous, solution comprising a sulfobetaine compound represented by formula (I) wherein: R1 is, an alkyl group having from 8 to 30 carbon atoms R2 and R3 are individually , hydrogen, or alkyl groups having from 1 to 4 carbon atoms and R4 is an alkyl group , having from 2 to 6 carbon atoms. In preferred embodiments of the invention the subject , compounds, are used in combination with antimicrobial agents for providing simultaneous disinfection and cleaning of contact lenses.
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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 January 30, 1997 and granted May 14, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended January 30, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by January 30, 2019.
- 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.