Cross-linked polymer composition for use in soft contact lenses
CA 1090937 A · Owner: Toray Industries, Inc. · Inventors: Hosaka, Shuntaro
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Provided is a cross-linked polymer composition which can be in a transparent polymeric gel form having an equilibrium water content of at least 60 wt.% for use in soft contact lenses. The cross-linked polymer composition is prepared by polymerizing, using a bulk polymerization procedure, a monomer mixture comprising an alkyl methacrylate and an N-vinyllactam in the presence of a cross-linking agent comprising at least one compound selected from vinyl acrylate, vinyl methacrylate, triallyl isocyanurate and vinyl carboxylates expressed by the formula: R?COOCH = CH2)n, where R is a hydrocarbon radical having 1 to 10 carbon atoms and n is an integer of 2, 3 or 4. - 1 -
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 December 2, 1980. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended December 2, 1997.
- 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.