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Expired Canadian patentCanada

Polytetrafluoroethylene porous material and process for producing the same

CA 2018389 C · Owner: Sumitomo Electric Industries, Ltd. · Inventors: Harada, Akira; Mano, Hiroshi

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

A polytetrafluoroethylene porous material and a process for producing the same are disclosed the material, comprising a mixture of polytetrafluoroethylene having a number-average molecular weight of 2,000,000 or more and polytetrafluoroethylene having a number-average molecular weight of 1,000,000 or less, the material having been stretched at least uniaxially.

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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 June 6, 1990 and granted July 30, 1996. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended June 6, 2010.
  • A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 6, 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.
FiledJune 6, 1990
GrantedJuly 30, 1996
Term endedJune 6, 2010
Patent numberCA 2018389 C
Classification (IPC)C08J9/00 +2 more

Timeline

Timeline From CIPO dates

1991199319951997199920012003200520072009Application filedJune 6, 1990Patent grantedJuly 30, 1996Term endedJune 6, 2010

Sources & verification

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