Donor-substituted oxindigo derivatives and their use as colourants
CA 2249217 A1 · Owner: Ciba Specialty Chemicals Holding Inc. · Inventors: Langhals, Heinz; Wagner, Barbara
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Oxindigo derivatives (1 and 2) in which four to seven of the radicals shown are hydrogen and one to four of these radicals are a radical chosen from the group consisting of a carbocyclic radical a heterocyclic radical, halogen, C1-, C18alkyl -OR12, -CN, -NR10R11, -COR9, -NR13COR9 -NR12COOR9, -NR12CONR10R11, -, NHSO2R9 -SO2R9, -SOR9, -SO2OR9, -CONR10R11, -SO2NR10R11 -N=NR14, -OCOR9 and -, OCONHR9, wherein two corresponding adjacent radicals can be combined to build up fused-on aromatic rings, in which R9 is C1-C18alkyl C6-C10aryl, benzyl or , a heterocyclic radical R10 and R11 are hydrogen, C1-C18alkyl, C3- to C24cycloalkyl, C6-C10aryl or heteroaryl or in which R10 and R11 together with …
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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 April 17, 1997. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended April 17, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 17, 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.