Patent Yard Sign in
Expired European patentEurope

Process for preparing alkaline earth metal salts of alkylbenzenesulfonic acids

EP 0016357 B1 · Applicant: HOECHST AKTIENGESELLSCHAFT

EPO PDF

Overview

The published document from the EPO: abstract, claims, description and drawings. Open it full size

Read the whole patent

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 February 26, 1980 and granted May 26, 1982. A European patent lasts at most 20 years from filing, so its term ended February 26, 2000.
  • 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 August 26, 2005.
  • 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.
FiledFebruary 26, 1980
PublishedOctober 1, 1980
GrantedMay 26, 1982
Term endedFebruary 26, 2000
Application numberEP 80100944
Classification (CPC)C07C309/00

Timeline

Timeline From EPO dates

1981198319851987198919911993199519971999Application filedFeb 26, 1980PublishedOct 1, 1980Patent grantedMay 26, 1982Term endedFeb 26, 2000

Sources & verification