Dyeing method using a specific active methylene compound and a compound selected among a specific aldehyde, a specific ketone, a quinone and a di-imino-isoindoline or 3-amino-isoindolone derivative

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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 December 22, 1999 and granted May 11, 2005. A European patent lasts at most 20 years from filing, so its term ended December 22, 2019.
• 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 June 22, 2025.
• 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.