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Expired European patentEurope

Toners treated with polymeric quaternary ammonium salts and slip agent and process

EP 0156369 B1 · Applicant: E.I. DU PONT DE NEMOURS AND COMPANY

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Listed from its EPO record in Patent Yard's archive of European patents past their term. Its claims, description and drawings are in the EPO PDF and on Google Patents, and the Claude kit works from them.

Why it's free to use

  • Filed March 27, 1985 and granted December 5, 1990. A European patent lasts at most 20 years from filing, so its term ended March 27, 2005.
  • A supplementary protection certificate, which can extend a medicine or crop-protection patent, adds at most five and a half years, so even that would have ended by September 27, 2010.
  • We check European rights only. A US or other national patent in its family could still be in force: check its family on Espacenet or Google Patents.
FiledMarch 27, 1985
PublishedOctober 2, 1985
GrantedDecember 5, 1990
Term endedMarch 27, 2005
Application numberEP 85103621
Classification (CPC)G03F7/28

Timeline

Timeline From EPO dates

1986198819901992199419961998200020022004Application filedMarch 27, 1985PublishedOct 2, 1985Patent grantedDec 5, 1990Term endedMarch 27, 2005

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