Optical recording medium
CA 2247338 C · Owner: Monden, Atsushi · Inventors: Shinkai, Masahiro; Monden, Atsushi; Kitagawa, Sumiko
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An optical recording medium is provided in which a recording layer contains a salt-forming dye between an ion of an azo metal complex of the following formula (I) and an ion of a cyanine dye of the following formula (II) having a, complex index of refraction in the wavelength region of recording light and/or reading light whose imaginary part k is up to 0.20, or at least one of azo oxovanadium metal complexes having an azo compound of the following formula (III) as a ligand and metal complexes having azo compounds of the following formulae (IV) and (V) as a ligand. Recording and reading can be carried out at a conventional wavelength or a short wavelength of about 630-690 nm or both. …
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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 December 22, 1997 and granted January 30, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended December 22, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 22, 2019.
- 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.