Optical recording medium
CA 2066835 A1 · Owner: Kitagawa, Nobuhisa · Inventors: Koike, Tadashi; Sasakawa, Tomoyoshi; Kitagawa, Nobuhisa
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An optical recording medium of a single plate type comprises a substrate, a recording layer overlying the substrate, a reflective layer overlying the recording layer, and a protective layer overlying the reflective layer, the recording layer being produced by coating a nonpolar solvent-soluble substituted phthalocyanine dye in a nonpolar solvent, and in the medium the content of the nonpolar solvent remaining in the recording layer being 5 % by weight or less.
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 April 22, 1992. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended April 22, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 22, 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.