Method for producing polyamides
CA 2277492 C · Owner: Oka, Hideaki · Inventors: Oka, Hideaki; Matsunaga, Susumu; Watanabe, Kazunori
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 polyamides and to a method for producing primary polycondensates which are intermediates for polyamide production. More precisely the invention relates to a method for producing primary polycondensates which comprises a step of polycondensing a dicarboxylic acid component having a terephthalic acid content of from 60 to 100 mol% and a diamine component in which the amount of 1,9-nonanediamine and/or 2-methyl-1,8-octanediamine falls between 60 and 100 mol% in the presence of water of being from 15 to 35 % by weight at a reaction temperature falling between 250°C and 280°C and under a reaction pressure (P) that satisfies the following formula …
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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 July 16, 1999 and granted May 7, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended July 16, 2019.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 16, 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.