Partially aromatic polyamides and a process for making them
CA 2304194 C · Owner: Dupont Canada Inc. · Inventors: Ng, Howard
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A process for making partially aromatic polyamides is provided in which an aromatic dicarboxylic acid component, at least 20-100 % by weight of the dicarboxylic acid in the acid component is in the form of an alkylated ester and a diamine component, comprising a diamine having from 6-12 carbon atoms are admixed in the presence of water and with heating to form polyamide having from 1-100 % on a molar basis of N-alkylated amide and amine groups. The polyamides are particularly useful in the manufacture of products intended for use at elevated temperatures or products in which retention of properties at elevated temperatures is required, including articles using injection moulding …
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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 September 24, 1998 and granted February 4, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended September 24, 2018.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by September 24, 2020.
- 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.