Process for preparing polybenzazole fibers by removing polyphosphoric acid
CA 2571384 C · Owner: E.I. Du Pont De Nemours And Company · Inventors: Lee, Kiu-Seung
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The present invention relates to polybenzazaole (PBZ) fibers and processes for removing polyphosphoric acid from a polybenzazole dope filament. The invention further relates to yarns, fabrics, and articles incorporating fibers of this invention, and processes for making such yarns fabrics, and articles.
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 July 20, 2005 and granted October 2, 2012. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended July 20, 2025.
- Certificates of supplementary protection extend only drug patents, and it isn't classified as one.
- 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.