Contact lens casting
CA 2048196 C · Owner: Van Houten, Norman M. · Inventors: Van Houten, Norman M.; Phoenix, John Thomas; Stafford, Peter Harold
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Hydrophobic casting moulds are treated with electrical discharge, such as corona discharge, to provide enhanced compatibility with hydrophilic objects introduced into the mould, without interfering with the release properties of the mould. A preferred embodiment involves treatment of contact lens casting moulds with corona discharge to provide improvements in the lens manufacturing procedure as well as, enhancement in the quality of the contact lenses themselves. The invention is particularly applicable to the production of contact lenses having a coloured iris pattern imprinted thereon.
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
- Filed July 31, 1991 and granted March 20, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended July 31, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 31, 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.
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.