Aqueous solutions of optical brighteners
CA 2600299 C · Owner: Clariant Finance (Bvi) Limited · Inventors: Tindal, Alec Stewart; Gauto, Mariela; Jackson, Andrew Clive
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The instant invention relates to storage stable aqueous solutions of stilbene optical brighteners with polyvinyl alcohols which can be directly used by the papermaker in that they may be diluted with water and/or be metered directly into a coating 5 composit ion, to provide coated papers of a particularly high whiteness.
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 5, 2006 and granted June 2, 2015. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 5, 2026.
- Certificates of supplementary protection extend only drug patents, and it isn't classified as one.
- 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.