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Expired Canadian patentCanada

Elastic polyurethane fiber

CA 2015739 C · Owner: Maeda, Katsura · Inventors: Maeda, Katsura; Yamashita, Setuo; Hirai, Koji

CIPO record

Overview

Drawings and full text

Its claims, description and drawings are in the Canadian Patents Database.

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Abstract From the Canadian patent

The present invention is directed to an elastic polyurethane fiber having excellent hot water resistance elastic recovery at low temperatures and elongation prepared from a polyurethane obtained by copolymerization of a high polymer diol obtained from 3-methyl-1,5-pentanediol and an aliphatic dicarboxylic acid, an organic diisocyanate and a chain extender.

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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 April 30, 1990 and granted February 2, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 30, 2010.
  • A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 30, 2012.
  • We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
FiledApril 30, 1990
GrantedFebruary 2, 1999
Term endedApril 30, 2010
Patent numberCA 2015739 C
Classification (IPC)D01F6/70 +2 more

Timeline

Timeline From CIPO dates

1991199319951997199920012003200520072009Application filedApril 30, 1990Patent grantedFeb 2, 1999Term endedApril 30, 2010

Sources & verification

Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.