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Expired European patentEurope

Process for purifying aqueous solutions of N-methyl-morpholine N-oxide

EP 0488988 B1 · Applicant: LENZING AKTIENGESELLSCHAFT

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Overview

The published document from the EPO: abstract, claims, description and drawings. Open it full size

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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 November 11, 1991 and granted September 15, 1993. A European patent lasts at most 20 years from filing, so its term ended November 11, 2011.
  • 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 May 11, 2017.
  • 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.
FiledNovember 11, 1991
PublishedJune 3, 1992
GrantedSeptember 15, 1993
Term endedNovember 11, 2011
Application numberEP 91890271
Classification (CPC)C02F1/281 +2 more

Timeline

Timeline From EPO dates

1992199419961998200020022004200620082010Application filedNov 11, 1991PublishedJune 3, 1992Patent grantedSep 15, 1993Term endedNov 11, 2011

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