| abstract |
A process for colouring a synthetic textile material or fibre blend thereof which comprises applying to the synthetic textile material a compound or mixture thereof, which is free from water solubilising groups, of the Formula (1) A-N=N-D, wherein: A and D each independently is an optionally substituted heterocyclic or carbocyclic group and at least one of A or D carries directly at least one -SO2F group or carries a substituent to which at least one -SO2F group is attached except for 4-(4-fluorosulphonylphenylazo)-N,N-dimethylaniline, provided that one of A or D is not 3,5-difluorosulphonylthien-2-yl, optionally substituted 1-phenyl-pyrazol-4-yl-5-one or (a) or that one of A or D does not carry an -NCH2CH(OH)CH2Cl, -NCOCH2Cl or -NCH2CH2SO2F substituent. The presence of one or more -SO2F groups in a dye molecule generally improves the properties of that dye and confers surprisingly good wet fastness and light fastness properties. |