Melt spinning of ultra-oriented crystalline filaments
CA 2083291 C · Owner: Cuculo, John A. · Inventors: Chen, Gao-Yuan; Lundberg, Ferdinand; Cuculo, John A.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Ultra-oriented, crystalline synthetic, filaments (2) with high tenacity are produced by extrusion of a fiber-forming synthetic polymer melt into a liquid isothermal bath (3) maintained at a temperature of at least 30°C above the glass transition temperature of the polymer, withdrawing the filaments from the bath and then winding up the filaments. Polyethylene terephthalate filaments so produced at 3000-5000 m/min exhibit a crystalline structure and possess birefringence of 0.20-0.22, tenacity of 6-8 g/dtex (7-9 g/d), break elongation of 14-30% and boil-off shrinkage of 5-10%.
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 15, 1991 and granted February 29, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended May 15, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 15, 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.