Water-absorptive polyurethane fiber and method of producing the same
CA 2243367 A1 · Owner: Nisshinbo Industries, Inc. · Inventors: Yoshida, Hiroshi; Uehara, Tsutomu; Sato, Takaya
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A water-insoluble, nonionic water-absorptive polyurethane fiber that combines the properties of high water absorptivity and excellent physical strength is produced by extrusion from a thermoplastic polyurethane resin composition at a temperature higher than its melting point. The thermoplastic polyurethane resin composition which has a water absorption rate within the range of 200-3,000%, is obtained by reacting a polyisocyanate compound a water-soluble polyalkylene ether polyol having an average molecular weight of 2,000-13,000 and a chain extender at an equivalent ratio (R ratio) between the equivalent number of NCO groups and the equivalent number of OH groups in the range of 1.0 to 1.8. …
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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 16, 1998. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended July 16, 2018.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 16, 2020.
- 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.