Multilayer blankout signs
CA 2059588 A1 · Owner: Ludwig, Edward Garland Jr. · Inventors: Ludwig, Edward Garland Jr.; Post, Robert Lee
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A novel light diffusing resin (material) has been invented which combines excellent light diffusing properties with high light transmission. The combination of properties is possible because the material does not significantly backscatter light. Also the material, exhibits good contact clarity. This light diffusing material is an excellent choice for use in blankout signs. A non-reflecting translucent white sheet is placed behind a transparent bronze overlay. The message is seen only when the sign is illuminated.
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 January 17, 1992. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended January 17, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by January 17, 2014.
- 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.