Process for preparing soap-acyl isethionate compositions
CA 2040451 C · Owner: Unilever Plc · Inventors: Podgorsky, Joseph J.; Richardson, David A.; Kutny, Yuriy O.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A batch and continuous process is disclosed for the production of a composition comprising alkali metal salts of C8-C22 alkyl fatty monocarboxylic acid and C8-C22 acyl isethionate in a ratio of 20:1 to 1:0.98. Both batch and continuous routes require that the saponifying aqueous caustic solution includes sodium hydroxide and sodium isethionate added as a hot solution. For the batch route, the sequence of steps requires the caustic solution to be added slowly to the fatty acid. In the continuous process, it is advantageous to introduce fatty acid upstream from the point where the caustic solution stream enters the mixing chamber. Addition of the acyl isethionate either precedes addition of …
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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 April 15, 1991 and granted June 9, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 15, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 15, 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.
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Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.