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Expired European patentEurope

Process for the preparation of highly concentrated, freely flowable, aqueous solutions of betaines

EP 0677509 B1 · Applicant: Witco Surfactants GmbH

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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 July 19, 1994 and granted January 14, 1998. A European patent lasts at most 20 years from filing, so its term ended July 19, 2014.
  • 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 January 19, 2020.
  • 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.
FiledJuly 19, 1994
PublishedOctober 18, 1995
GrantedJanuary 14, 1998
Term endedJuly 19, 2014
Application numberEP 94111215
Classification (CPC)C07C231/12 +2 more

Timeline

Timeline From EPO dates

1995199719992001200320052007200920112013Application filedJuly 19, 1994PublishedOct 18, 1995Patent grantedJan 14, 1998Term endedJuly 19, 2014

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