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Expired European patentEurope

Process for making a fully-crystalline silicon nitride sintered body

EP 0171444 B1 · Applicant: Hutschenreuther AG

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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.

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Why it's free to use

  • Filed August 11, 1984 and granted June 1, 1988. A European patent lasts at most 20 years from filing, so its term ended August 11, 2004.
  • 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 February 11, 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.
FiledAugust 11, 1984
PublishedFebruary 19, 1986
GrantedJune 1, 1988
Term endedAugust 11, 2004
Application numberEP 84109589
Classification (CPC)C04B35/597 +1 more

Timeline

Timeline From EPO dates

1985198719891991199319951997199920012003Application filedAug 11, 1984PublishedFeb 19, 1986Patent grantedJune 1, 1988Term endedAug 11, 2004

Sources & verification

Official EPO records

Full published documentClaims, description and drawings as a PDF.EPOEuropean Patent RegisterProcedure, status, file inspection and legal events.EPOLinked open EP data recordThe bibliographic record this page is built from.EPO

Cross-check elsewhere

Google PatentsFull text, worldwide family, citing patents and legal events.patents.google.comEspacenetNational family members and their legal status.European Patent Office

Everything on this page comes from the EPO record linked above. EPO data used under CC BY 4.0.