Continuous process for the production of polyamides
CA 2523545 C · Owner: E.I. Du Pont De Nemours And Company · Inventors: Etchells, Arthur William, Iii; Mallon, Frederick K.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
In a two-step precondensate process for preparing polyamides diamines are reacted with dicarboxylic acid dihalides in a polar non-basic, inert organic , liquid medium under conditions such that a condensation product having a low degree of polymerization is formed. The resulting condensation then is contacted with an aqueous solution of a water-soluble acid acceptor by continuously feeding the components into a reactor system having a total residence time from about 2 seconds to about 2 minutes and having a Peclet , number greater than about 3.5 to form a polyamide product having a high degree of polymerization.
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 May 12, 2004 and granted January 17, 2012. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended May 12, 2024.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 12, 2026.
- 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.