Method for producing hexanediol-1,6
CA 2331817 A1 · Owner: Iffland, Gabriele · Inventors: Krug, Thomas; Stein, Frank; Gall, Martin
Overview
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 for producing hexanediol-1,6 from a carboxylic acid mixture containing adipic acid 6-hydroxycaproic acid and , small amounts of 1,4-cyclohexanediols said mixture being obtained as a by-, product of the oxidation of cyclohexane to form cyclohexanon/cyclohexanol with oxygen or gases containing oxygen and through the water-extraction of the reaction mixture, by means of esterification of the acids and hydrogenation. The method comprises the following steps: a) converting the mono- and dicarboxylic acids contained in the aqueous dicarboxylic acid mixture to the corresponding carboxylic acid esters with a low-molecular alcohol; b) liberating the resulting …
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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 May 10, 1999. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended May 10, 2019.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 10, 2021.
- 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.