Thermal and photochemical stabilization of dyeings on polyamide fibers:sterically hindered phenol and ultra-violet absorber

A process for improving the thermal and/or photochemical stability of dyed polyamide fibres, which comprises treating the fibres with an agent from an aqueous bath containing

• (A) a water-soluble compound of the formula
• (A--Y--).sub.n Z(--W).sub.m ( 1)
• in which A is the radical of a sterically hindered phenol from the benzene series, Y is a radical of the formulae (2) or (3) ##STR70## in which X and X', independently of one another, are alkylene, oxaalkylene or thiaalkylene, R.sub.2 and R.sub.3, independently of one another, are hydrogen or a substituted or unsubstituted alkyl group and x,x' and y, independently of one another, are each 0, or 1, Z is an aliphatic or a carbocyclic aromatic radical, the latter containing at most two mono- or bicyclic rings, W is a sulfo group and m and n, independently of one another, are 1 or 2, and their water-soluble salts, and
• (B) a UV absorber,
• wherein the compound of formula (1) and the UV absorber goes onto the fibers by an exhaust or continuous dyeing process.