Use of reactive dyes for dyeing hair
CA 2294007 A1 · Owner: Patsch, Manfred · Inventors: Hossel, Peter; Patsch, Manfred; Prechtl, Frank
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The invention relates to the use of reactive dyes for dyeing hair. Said reactive dyes are of formula (I), wherein a represents 1 or 2 b represents 0 , or 1, Y represents vinyl or a radical of formula C2H4Q Q being a group which , can be split off in alkaline reaction conditions L3 represents a direct bond , or a binding link of formula CO-NH-M1 which can be interrupted by 1 or 2 nonadjacent oxygen atoms, imino or C1-C4 alkylimino groups M1 being C2-C6 , alkylene, A1 represents hydroxysulfonyl or a radical of formula SO2Y A2 , represents hydrogen, hydroxysulfonyl methoxy, chlorine, bromine or carboxyl W represents 1) the radical of a coupling constituent of a monoazo dye or , additionally, …
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 July 3, 1998. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended July 3, 2018.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 3, 2020.
- 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.