Patent ID: 7144451

Claim:
A method of printing sheet-form substrates by the inkjet printing process, which method comprises printing those materials with an aqueous ink comprising a) at least one dye of formula wherein R 1 and R 2 are each independently of the other hydrogen or unsubstituted or substituted C 1 –C 4 alkyl, R 3 and R 4 are each independently of the other unsubstituted or substituted C 1 –C 4 alkyl, R 5 and R 6 are each independently of the other C 1 –C 4 alkyl, C 1 –C 4 alkoxy, halogen, hydroxy, C 2 –C 4 alkanoylamino or sulfo, X is halogen, hydroxy, C 1 –C 4 alkoxy that is unsubstituted or substituted in the alkyl moiety, phenoxy that is unsubstituted or substituted in the phenyl ring, C 1 –C 4 alkylthio that is unsubstituted or substituted in the alkyl moiety, phenylthio that is unsubstituted or substituted in the phenyl ring, amino, N-mono- or N,N-di-C 1 –C 6 alkylamino that is unsubstituted or substituted in the alkyl moiety and uninterrupted or interrupted in the alkyl moiety by oxygen, C 5 –C 7 cycloalkylamino that is unsubstituted or substituted in the cycloalkyl ring, phenyl- or naphthyl-amino that is unsubstituted or substituted in the aryl moiety, N—C 1 –C 4 alkyl-N-phenyl- or N—C 1 –C 4 alkyl-N-naphthyl-amino that is unsubstituted or substituted in the aryl moiety, benzylamino that is unsubstituted or substituted in the phenyl moiety, morpholino or piperidin-1-yl, and n and m are each independently of the other the number 1, 2 or 3; and b) a solubiliser or a humectant selected from the group consisting of polyethylene glycols having a molecular weight of from 150 to 400.