Erasable optical media
CA 2129232 A1 · Owner: Parkinson, Dean B. · Inventors: Parkinson, Dean B.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
of the Invention, The invention relates to a novel information recording medium and the recording of information thereon. The recording medium material possesses both retention and expansion characteristics suitable for use with optical recording,reading and erasing systems.
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 February 18, 1994. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended February 18, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by February 18, 2016.
- 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.