Process for producing plastic lens
CA 2018908 C · Owner: Mase, Shoji · Inventors: Mase, Shoji; Otani, Noboru; Yoshida, Motoaki
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A process for producing a plastic lens is disclosed, which comprises the steps of: providing a primer layer comprising a polyurethane on the surface of a plastic lens substrate; subsequently providing a hard coat layer comprising a silicone resin on the surface of the primer layer; and then providing a single-layer or multi-layer anti-reflection coating on the surface of the hard coat layer by depositing an inorganic material wherein the polyurethane used for providing the primer layer is a thermosetting polyurethane.
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 June 13, 1990 and granted November 9, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended June 13, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 13, 2012.
- 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.