Disazo dyes, and copper complexes thereof, for dyeing paper
CA 2431043 A1 · Owner: Lautenbach, Holger · Inventors: Kaser, Adolf; Lautenbach, Holger
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The dyes of formula (1) according to claim 1 and the copper complexes of dyes of formula (2) according to claim 9 or the mixtures of mono-copper complex with the bis-copper complex are excellently suitable for dyeing paper with good light-fastness properties.
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 December 19, 2001. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended December 19, 2021.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 19, 2023.
- 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.