Magnetooptical recording media
CA 2000808 A1 · Owner: Mitsui Petrochemical Industries Ltd. · Inventors: Kajiura, Hirokazu; Mizumoto, Kunihiko; Haruta, Koichi
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
In accordance with the present invention there are, provided magnetooptical recording media having on a substrate at least an enhancement film (I) and a magnetooptical recording film (II), said enhancement film (I) being composed of a silicon nitride film represented by SiNx (wherein 0<x<1.33) and having a refractive index n of at least 1.9, and said magnetooptical recording film being composed of an amorphous alloy film represented by PdaPt1-ayREbTM1-b1-y(wherein at least 50 atom% of RE is Tb and/or Dy, the remainder is Nd Gd, Ce, Eu, Pr, Ho, Tm or Sm, TM is Fe and/or Co and 0?a?1, 0.2<b<0.7 and, 0.05?y?0.3) and having a magnetic easy axis perpendicular to the film. These magnetooptical …
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 October 16, 1989. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended October 16, 2009.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 16, 2011.
- 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.