Method for stabilizing an agent for contact lenses
CA 2114747 C · Owner: Nakayama, Hisayuki · Inventors: Nakayama, Hisayuki; Kimoto, Akihiro; Tsuchino, Kuniko
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method for stabilizing an agent for contact lenses containing a proteolytic enzyme by adding a surfactant to a solution containing an effective amount of a proteolytic enzyme the production of a lyophilized agent for contact lenses containing a proteolytic enzyme, which comprises subjecting an aqueous composition containing a proteolytic enzyme to a lyophilizing treatment in the presence of a surfactant and a, lyophilized agent for contact lenses which contains a proteolytic enzyme and a surfactant. The method of the present invention enables stable preservation of a proteolytic enzyme in a liquid form. In addition, cleaning, sterilization and preservation can be simultaneously performed …
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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 February 2, 1994 and granted March 16, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended February 2, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 2, 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.