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Expired European patentEurope

Process for the recovery and recycling of an oxydation catalyst in the Witten DMT process

EP 0020990 B1 · Applicant: HÜLS TROISDORF 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 May 12, 1980 and granted September 12, 1984. A European patent lasts at most 20 years from filing, so its term ended May 12, 2000.
  • 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 November 12, 2005.
  • 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.
FiledMay 12, 1980
PublishedJanuary 7, 1981
GrantedSeptember 12, 1984
Term endedMay 12, 2000
Application numberEP 80102628
Classification (CPC)C07C67/08 +2 more

Timeline

Timeline From EPO dates

1981198319851987198919911993199519971999Application filedMay 12, 1980PublishedJan 7, 1981Patent grantedSep 12, 1984Term endedMay 12, 2000

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