A process for the preparation of a water soluble direct green polyazo dyestuffs mixture in situ and water soluble direct green polyazo dyestuffs mixture obtained thereby

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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 24, 1986 and granted November 7, 1990. A European patent lasts at most 20 years from filing, so its term ended July 24, 2006.
• 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 24, 2012.
• 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.