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Expired European patentEurope

Alumina-zirconia-silicon carbide-magnesia compositions and cutting tools

EP 0449844 B1 · Applicant: KENNAMETAL INC.

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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 October 13, 1989 and granted November 24, 1993. A European patent lasts at most 20 years from filing, so its term ended October 13, 2009.
  • 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 April 13, 2015.
  • 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.
FiledOctober 13, 1989
PublishedOctober 9, 1991
GrantedNovember 24, 1993
Term endedOctober 13, 2009
Application numberEP 89912753
Classification (CPC)C04B35/645 +1 more

Timeline

Timeline From EPO dates

1990199219941996199820002002200420062008Application filedOct 13, 1989PublishedOct 9, 1991Patent grantedNov 24, 1993Term endedOct 13, 2009

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