Process for preparing polyvinyl alcohol yarn
CA 1301418 C · Owner: Vos, Gerardus J.H. · Inventors: Smook, Jan; Van Hees, Theodorus J.; Vos, Gerardus J.H.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A yarn having a viscosity average molecular weight ?v in the range of 105 to 4.105 is produced by extruding and drawing a solution of polyvinyl alcohol in an organic solvent, from a spinneret into a coagulation bath through an air gap or inert gas gap. The length of the capillaries of the spinneret in the direction of flow is at least 5 times their diameter and the concentration C in % by weight of the polymer solution is so selected that C ? 30 - 5.10-5 ?v.
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
- Granted May 26, 1992. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended May 26, 2009.
- 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.