Method of producing polytrimethylene terephthalate staple fibers
CA 2433005 A1 · Owner: Yamada, Toshihiro · Inventors: Yamada, Toshihiro
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method for producing polytrimethylene terephthalate short fiber which , comprises melt-spinning a polytrimethylene terephthalate based polymer taking , the spun fiber off via a take-up roller holding the fiber as an unstretched , tow in a can under a such a condition that the undrawn tow has a water content of 0.5 to 12 wt % and the the circumstance around the undrawn tow has a temperature of 35 ~ C or lower, and then subjecting the tow to a drawing step.
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 October 23, 2002. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended October 23, 2022.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 23, 2024.
- 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.