Solid compositions containing amine oxide-maleic acid salts
CA 2187442 C · Owner: Young, Raymond Devon · Inventors: Young, Raymond Devon; Wierenga, Thomas James
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Disclosed are solid, concentrated, amine oxide surfactant compositions containing amine oxide-maleic acid salts. The molar ratio of maleic acid to amine oxide in such salts is about a 1:1. The salts are soluble in water at 25° C at a pH of above the pKa of the amine oxide. Also disclosed is a process for preparing such solid amine oxide surfactant compositions which process comprises admixing maleic acid and amine oxide surfactants in at least about a 1:1 molar ratio at a pH of at least about 1 unit less than the pKa of the amine oxide to, thereby form a visible precipitate therein. The precipitate is separated from the mixture preferably by mechanical means, and dried. The dried …
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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 November 30, 1994 and granted July 27, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended November 30, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 30, 2016.
- 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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Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.