Birefringent marking
CA 2498417 A1 · Owner: Schmitzer, Siegfried · Inventors: Patrick, John; Hammond-Smith, Robert; Schmelz, Michael
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The invention relates to a method of preparing a birefringent marking by printing a polymerisable liquid crystal material onto at least one side of a substrate and polymerising the liquid crystal material to a birefringent , marking obtained by this method and to the use of the birefringent marking for decorative, security, authentification and identification applications.
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 August 8, 2003. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended August 8, 2023.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 8, 2025.
- 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.