Ultraviolet blocking agents for contact lenses
CA 1286833 C · Owner: Park, Joon S. · Inventors: Bambury, Ronald E.; Choo, Dong J.; Park, Joon S.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A contact lens comprises a polymer formed by copolymerizing a first monomer suitable for use in making such lenses and a copolymerizable monomeric ultraviolet absorber. The improvement comprises employing as the monomeric ultraviolet absorber about 0.25% to about 2% by weight of a compound selected from the group of compounds having the formula: wherein R is Cl or OCH3.
Read the whole patent
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 July 23, 1991. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended July 23, 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.