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Expired Canadian patentCanada

Process for hydrating soft contact lenses

CA 2040520 C · Owner: Vistakon, Inc. · Inventors: Kindt-Larsen, Ture

CIPO record

Overview

Drawings and full text

Its claims, description and drawings are in the Canadian Patents Database.

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Abstract From the Canadian patent

A process for releasing leachable substances from a polymeric contact lens blank. The contact lens is confined in a cavity within a carrier to permit the hydration of the lens without permitting it to invert or roll over. A fluid flow is introduced into the cavity about the lens to extract leachable material from the lens. The process significantly reduces the amount of leaching fluid that is used and the amount of time that is needed for hydration washing and extraction.

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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 15, 1991 and granted June 16, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 15, 2011.
  • A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 15, 2013.
  • 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 15, 1991
GrantedJune 16, 1998
Term endedApril 15, 2011
Patent numberCA 2040520 C
Classification (IPC)B44C1/22 +2 more

Timeline

Timeline From CIPO dates

1992199419961998200020022004200620082010Application filedApril 15, 1991Patent grantedJune 16, 1998Term endedApril 15, 2011

Sources & verification

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