Blue dye with particularly high purity and positive triboelectric control effect
CA 2500803 A1 · Owner: Clariant Gmbh · Inventors: Macholdt, Hans-Tobias; Michel, Eduard; Baur, Rudiger
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The dye base sulphate of formula (I) is produced with a residual amine content of less than 2000 ppm, as determined by HPLC by precipitation of the dye , base, made by Friedel-Crafts alkylation substitution and hydrolysis, as the , dye base sulphate and a) taken up in water and subjecting to a first steam distillation then filtered and optionally dried at 50 to 180 ~C b) the , pressed cake is treated with water or the optionally dried dye base sulphate is moistened with water, c) subjected to a further steam distillation and filtration and d) dried at 50 to 180 ~C.
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 21, 2003. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended October 21, 2023.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 21, 2025.
- 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.