Expired Canadian patentCanada
Method of straightening hair with compositions comprising an alpha-hydroxy acid and a reducing agent
CA 2534548 C · Owner: Unilever Plc · Inventors: Tiwari, Laxmikant
Overview
Drawings and full text
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The invention relates to a method of lengthening hair comprising the step of applying a non-oxidative composition comprising an a -hydroxy acid and/or its salt and a reducing agent preferably having the following formula:
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 August 27, 2004 and granted July 31, 2012. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended August 27, 2024.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 27, 2026.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
FiledAugust 27, 2004
GrantedJuly 31, 2012
Term endedAugust 27, 2024
Patent numberCA 2534548 C
Classification (IPC)A61K8/49 +2 more
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.