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Expired Canadian patentCanada

Composition and method for inhibiting the deposition of protein on contact lens

CA 2253840 C · Owner: Heiler, David J. · Inventors: Heiler, David J.; Maier, Stephen E.; Spooner, Susan P.

CIPO record

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Abstract From the Canadian patent

The invention is directed to compositions and methods used as in-the-eye and/or out-of-eye inhibitors of proteinaceous deposits on hydrophilic contact lenses. Compositions of the present invention comprise moderately charged polyquaternium polymers that selectively bind to hydrophilic contact lenses to block the binding of proteinaceous materials. Compositions of the present invention may be used in multipurpose cleaning solutions for contact lenses and can eliminate the need for special enzyme cleaners and the like for removing proteinaceous materials.

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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 April 30, 1997 and granted February 18, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 30, 2017.
  • A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 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.
FiledApril 30, 1997
GrantedFebruary 18, 2003
Term endedApril 30, 2017
Patent numberCA 2253840 C
Classification (IPC)C11D3/37 +2 more

Timeline

Timeline From CIPO dates

1998200020022004200620082010201220142016Application filedApril 30, 1997Patent grantedFeb 18, 2003Term endedApril 30, 2017

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Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.