Azo dyestuffs
CA 1070297 A · Owner: Sandoz Ltd. · Inventors: Dore, Jacky
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The present invention relates to asymmetric 1:2 chromium complexes of formula I, I, in which A is a group of formula (a) or (b) or , (a) (b), in which X is halogen, nitro or methyl Y is hydrogen or nitro, * designates the carbon atom bound to the azo group, Z is halogen or nitro, both substituents being the same, each of R1 and R2, independently is unsubstituted phenyl or phenyl substituted by a total of up to three substituents selected from halogen, (C1-6) alkyl, (C1-6) alkoxy, nitro and cyano (maximum of two nitro and/or cyano), and, M is hydrogen or an equivalent of a nonchromophoric cation, with the proviso that the sulpho group is in salt form and mixtures of two or more of such 1:2 …
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
- Granted January 22, 1980. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended January 22, 1997.
- 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.