Dual status thin-film eas marker
CA 2109643 C · Owner: Minnesota Mining And Manufacturing Company · Inventors: Tsai, Ching-Long
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A dual status marker for use with a magnetic-type EAS system has a signal-producing layer including at least one magnetic thin-film of high permeability and low coercive force such as permalloy, and a signalblocking layer including at least one remanently magnetizable thin-film such as an Fe-Cr alloy. The remanently magnetizable thin-film or thin-films should have a total thickness at least equal to and, preferably at least twice, the total thickness of the magnetic thin-film or thin-films of high permeability. By doing so the marker is more reliably deactivated when the signal-blocking layer is magnetized. For even greater assurance of deactivation, the signal-blocking layer should include …
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 November 22, 1993 and granted March 26, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended November 22, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 22, 2015.
- 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.