Triphendioxazine dyestuffs

A dyestuff of the formula ##STR60## wherein B=CH.dbd.CH.sub.2 or CH.sub.2 CH.sub.2 W,

• wherein
• W=detachable group, selected from the group consisting of OSO.sub.3 H, Cl, S.sub.2 O.sub.3 H,
• OCOCH.sub.3, OPO.sub.3 H.sub.2 and --N(CH.sub.3).sub.3,
• R=H or C.sub.1 -C.sub.4 -alkyl
• optionally substituted by OH, OCH.sub.3, COOH or SO.sub.3 H,
• Z=reactive group or H,
• T.sub.1 and T.sub.2 stand for H, Cl, Br, C.sub.1 -C.sub.4 -alkoxy, C.sub.1 -C.sub.4 alkyl, optionally substituted phenyl or phenoxy, each optionally substituted by Cl, CH.sub.3, C.sub.2 H.sub.5, OCH.sub.3 or OC.sub.2 H.sub.5,
• X stands for O, S or ##STR61## Y stands for phenylene optionally substituted by SO.sub.3 H, CH.sub.3 or COOH, ##STR62## cyclohexylene, in aliphatic hydrocarbon radical optionally substituted by phenyl --SO.sub.3 H, COOH, COCH.sub.3 or OSO.sub.3 H or an aliphatic hydrocarbon radical interrupted by an oxygen or sulfur atom, N--H or NCOCH.sub.3 or
• X and Y together stand for a direct bond or ##STR63## R' stands for Cl, Br, SO.sub.3 H, C.sub.1 -C.sub.4 -alkyl, C.sub.1 -C.sub.4 -alkoxy or COOH,
• R" stands for hydrogen or C.sub.1 -C.sub.4 -alkyl and in the event that Y denotes an optionally substituted divalent aliphatic radical together with R also stands for alkylene, n denotes 0 or 1 and wherein the radical SO.sub.2 B is in ortho-position relative to the substituent ##STR64##