Dyeing leather with dyes containing vinylsulfonyl, or precursor, reactive groups, useful e.g. for making gloves or clothing, by treatment with dye liquor at pH at least 7.5

摘要

Method for dyeing leather with at least one dye (I) that contains a group (A) activatable under alkaline conditions, comprises treating it with an aqueous liquor containing (I) at pH at least 7.5. Method for dyeing leather with at least one dye (I) that contains a group of formula (A) activatable under alkaline conditions, comprises treating it with an aqueous liquor containing (I) at pH at least 7.5. [Image] X : electron-withdrawing substituent; k : 1-3; n : 0 or 1; B : vinyl or CH 2CH 2Q; Q : group that is cleaved under alkaline conditions; the dotted line indicates the bond to the dye molecule. Independent claims are also included for the following: (1) new dyes of formulae (IIa), (IIIa), (IVa) and (IIb); and (2) leather dyed by the new method. Dk 1>-N=N-Napht 1>-N=N-Tk 1>-[N=N-Kk 1>] k-N=N-Dk 2> (IIa) Dk 1>-N=N-Napht 1>-N=N-Tk 1>-N=N-Kk 1>-N=N-Tk 2>-N=N-Napht 2>-N=N-Dk 2> (IIIa) Dk 1>-N=N-Napht 1>-N=N-Tk 1>-N=N-Napht 2>-N=N-Dk 2> (IVa) A-N=N-Napht 1>-N=N-Tk 1>-N=N-Kk 1>-[N=N-Dk 2>] n (IIb). k and n : 0 or 1; Dk 1> and Dk 2>residue of an aromatic amine or group (A), provided at least one is A; Kk 1>residue of specified couplers; Tk 1> and Tk 2>divalent aromatic residues. The full definitions are given in the DEFINITIONS (Full Definitions) Field.