Abstract: Fibre-reactive formazan compounds, salts thereof or free acid forms thereof according to formula (I) ##STR1## in which R.sub.1 is hydrogen or --COOH, each of R.sub.2 and R.sub.4 is independently hydrogen, --COOH, --SO.sub.3 H, --NHCOCH.sub.3, --NHCOCHY.sub.2 --CH.sub.2 Y.sub.1, --NHCOCY.sub.2 .dbd.CH.sub.2 or --NHCOCH.sub.2 Y.sub.1,R.sub.3 is hydrogen, halogen, C.sub.1-4 alkyl, C.sub.1-4 alkoxy, --COOH or --SO.sub.3 H,Y.sub.1 is chlorine, bromine, --OSO.sub.3 H or --SSO.sub.3 H,Y.sub.2 is hydrogen, chlorine or bromine, andZ is ##STR2## The compounds are particularly useful in dyeing or printing hydroxy-group containing or nitrogen-containing organic substrates, including leather, fiber materials, and textiles.

Abstract: Metal-free compounds of the formula ##STR1## a 1:1 or 1:2 metal complex of a metallizable compound of said formula or a salt of a metal-free compound of said formula or of a 1:1 or 1:2 metal complex thereof each cation of which is independently a non-chromophoric cation, or a mixture, thereof, whereinF.sub.c is the radical of a water-soluble azo, formazan, phthalocyanine, azomethine, oxazine, thiazine, phenazine or triphenylmethane dye,each W is independently --NR.sub.1 --B.sub.1 --NR.sub.1 --, ##STR2## wherein B.sub.1 is linear or branched C.sub.2-6 alkylene; linear or branched C.sub.2-6 alkylene interrupted by --O-- or --NR.sub.1 --; linear or branched C.sub.3-6 alkylene monosubstituted by hydroxy or carboxy or disubstituted by hydroxy, ##STR3## wherein R.sub.2 is hydrogen, C.sub.1-4 alkyl, C.sub.1-4 alkoxy, carboxy or sulfo, andn is 0, 1, 2, 3 or 4, andm is 0 or 1,each X is independently a direct bond, --CO-- or --SO.sub.

Abstract: Compounds of the formula ##STR1## and salts thereof, and their use as as reactive dyes for the dyeing and printing of hydroxy group- and nitrogen- containing organic substrates, e.g., leather, natural and synthetic polyamides and natural and regenerated cellulose.