Primary intermediates for oxidative coloration of hair
CA 2431611 A1 · Owner: P&G-Clairol, Inc. · Inventors: Pan, Yuh-Guo; Lim, Mu-Ill
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Primary intermediates for hair coloring compositions for oxidative dyeing of hair are compounds of the formula (1): wherein R1 and R2 are aech independently selected from hydrogen atoms a C1 to C5 alkyl or hydroxyalkyl , group or R1 and R2 together with the nitrogen atom to which they are attached form a 5 or 6 member cyclic ring optionally containing one or more additional atoms selected from O, N or S atoms, and n is equal to 1 or 2 with the , proviso that when n is equal to 2 only one of R1 and R2 may be hydrogen.
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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 January 18, 2002. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended January 18, 2022.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by January 18, 2024.
- 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.