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Expired European patentEurope

Use of water-insoluble aluminium silicates in the tanning of leather by chromium compounds

EP 0005546 B1 · Applicant: Henkel Kommanditgesellschaft auf Aktien

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Overview

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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 17, 1979 and granted June 23, 1982. A European patent lasts at most 20 years from filing, so its term ended May 17, 1999.
  • 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 17, 2004.
  • 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 17, 1979
PublishedNovember 28, 1979
GrantedJune 23, 1982
Term endedMay 17, 1999
Application numberEP 79101513
Classification (CPC)C14C3/02 +1 more

Timeline

Timeline From EPO dates

1980198219841986198819901992199419961998Application filedMay 17, 1979PublishedNov 28, 1979Patent grantedJune 23, 1982Term endedMay 17, 1999

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