Patent ID: 7527656

Claim:
A process for enhancing the thermal, oxidative and photochemical stability of dyed or printed fiber material, wherein the fiber material is in the form of yarns, carpets, non-woven or woven fabrics or knitted fabrics, which comprises treating the fiber material, before, during or after a dyeing or printing step in an aqueous medium, with a stabilizer mixture which comprises at least one compound of the formula and at least one compound of the formula in which R 1 and R 1 ′ independently of one another are each linear or branched C 1 -C 18 alkyl, C 3 -C 8 cycloalkyl, C 3 -C 6 alkenyl, unsubstituted or substituted aryl or C 7 -C 12 aralkyl, R 2 , R 2 ′, R 3 , R 3 ′, R 4 and R 5 independently of one another are each hydrogen, unsubstituted or substituted, linear or branched C 1 -C 12 alkyl, or linear or branched C 4 -C 28 alkyl, which is interrupted by one or more N, S or O atoms and which may be substituted further or are a radical —CO—R 6 or —SO 2 —R 6 , and R 6 is C 1 -C 12 alkyl, unsubstituted or C 1 -C 4 alkyl-substituted phenyl or C 7 -C 12 aralkyl and wherein the fiber material consists of polyamide fibers.