Polymeric whitening agent
CA 2057200 C · Owner: Unilever Plc · Inventors: Khorshahi, Ferial; Aronson, Michael Paul; Langer, Matthew Evan
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The present invention pertains to polymeric whitening agents which contain both a fluorescent portion and a hydrophilic portion. These copolymers may be used on certain substrates such, as polyester or soiled cottons, for a greater brightening then previously known.
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 December 6, 1991 and granted May 20, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended December 6, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 6, 2013.
- 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.