Drawable high tensile strength aramids
CA 2040302 A1 · Owner: E. I. Du Pont De Nemours And Company · Inventors: Irwin, Robert S.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Aramids which after drawing have high tensile strengths and tensile moduli are made from units derived from selected 2,2'-disubstituted-4,4'-diaminobiphenyls p-phenylenediamine, oxydianiline and terephthalic acid. Also disclosed is a process for drawing such aramids at least 1.5%, which results in the drawn aramid having significant crystallinity and higher tensile strength. The aramids are useful for ropes and composites.
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 April 12, 1991. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended April 12, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 12, 2013.
- 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.