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Expired European patentEurope

Recovery of acrylic acid and/or ethyl acrylate from black acid

EP 0455906 B1 · Applicant: HOECHST CELANESE CORPORATION

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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.

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Why it's free to use

  • Filed October 11, 1990 and granted January 18, 1995. A European patent lasts at most 20 years from filing, so its term ended October 11, 2010.
  • 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 11, 2016.
  • 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 11, 1990
PublishedNovember 13, 1991
GrantedJanuary 18, 1995
Term endedOctober 11, 2010
Application numberEP 90311164
Classification (CPC)C07C67/04 +1 more

Timeline

Timeline From EPO dates

1991199319951997199920012003200520072009Application filedOct 11, 1990PublishedNov 13, 1991Patent grantedJan 18, 1995Term endedOct 11, 2010

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

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