Use of unsaturated aldehydes in dying fibers containing keratin
CA 2288055 A1 · Owner: Moeller, Hinrich · Inventors: Hoeffkes, Horst; Moeller, Hinrich
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 unsaturated aldehydes of formulae (Ia) or (Ib), wherein R1, R2, R3 and R4 independently mean hydrogen halogen, a C1-C4-, alkoxy, C1-C4-alkyl aryl radical or a C1-C4-alkoxy-C1-C4-aryl radical and n stands for 1 or 2, wherein R1 and R2, R1 and R3 R2 and R3 and R2 and R4 can , form together with a residual molecule a ring with 5 to 7 units when n equals 1, in addition to the corresponding mono bis or .omega.-alkoxy acetals, for , the dying of fibers containing keratin specially human hair.
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 April 16, 1998. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended April 16, 2018.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 16, 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.