Patent Yard Sign in
Expired European patentEurope

Production of high-quality aromatic amino azo compounds by the rearrangement of 1,3-diaryl triazenes

EP 0013643 B1 · Applicant: E.I. DU PONT DE NEMOURS AND COMPANY

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.

Google PatentsEPO PDF

Why it's free to use

  • Filed January 7, 1980 and granted December 8, 1982. A European patent lasts at most 20 years from filing, so its term ended January 7, 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 July 7, 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.
FiledJanuary 7, 1980
PublishedJuly 23, 1980
GrantedDecember 8, 1982
Term endedJanuary 7, 2000
Application numberEP 80400015
Classification (CPC)C07C245/24

Timeline

Timeline From EPO dates

1981198319851987198919911993199519971999Application filedJan 7, 1980PublishedJuly 23, 1980Patent grantedDec 8, 1982Term endedJan 7, 2000

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.