Process for dyeing wool-containing fibre materials

A process for dyeing wool-containing fibre materials with anionic dyes, which comprises dyeing said materials in the presence of a wool protective agent containing at least one compound of formula ##STR11## wherein R and R' are each independently of the other hydrogen, C.sub.1 -C.sub.6 alkyl or a cation, R.sub.1, R.sub.2, R.sub.1 ' and R.sub.2 ' are each independently of one another hydrogen, C.sub.1 -C.sub.6 alkyl or halogen,

• B is a radical of formula
• --X--Z.sub.1 -- (2a),
• --X--Z.sub.2 -- (2b) or
• --NR.sub.3 --(alk)--Z.sub.1 --(alk).sub.0-1 --NR.sub.3 '-- (2c),
• X is a functional group --O-- or --NR.sub.3 --,
• R.sub.3 and R.sub.3 ' are each independently of the other hydrogen or C.sub.1 -C.sub.6 alkyl,
• Z.sub.1 is a radical of formula
• --(CH.sub.2 --CH.sub.2 --O).sub.p --(CHY.sub.1 --CHY.sub.2 --O).sub.q --(CHY.sub.3 --CHY.sub.4 --O).sub.r -- (3),
• one of Y.sub.1 and Y.sub.2 is methyl and the other is hydrogen,
• one of Y.sub.3 and Y.sub.4 is ethyl and the other is hydrogen,
• p, q and r are each independently of each other an integer from 0 to 20, and the sum of (p+q+r) is from 2 to 20,
• Z.sub.2, if X is --NR.sub.3 --, is the radical of a tri-, tetra- or polyamine, whose free amino groups are partially or completely in the form of an acylamino group of formula
• --NR.sub.3 --CO--CR.sub.1 ".dbd.CR.sub.2 "--CO--O--R" (4a),
• or, if X is --O--, is the radical of a tri-, tetra- or polyol, whose free hydroxyl groups are partially or completely in the form of an ester group of formula
• --O--CO--CR.sub.1 ".dbd.CR.sub.2 "--CO--O--R" (4b),
• R" independently has the meaning of R, and R.sub.1 " and R.sub.2 " have each independently of the other the meaning of R.sub.1 and R.sub.2, and
• (alk) is a C.sub.1 -C.sub.4 alkylene radical which is further unsubstituted or substituted.