Patent ID: 6875831

Claim:
A compound of formula (I), (II) or (III) wherein R 1 and R 2 are independently of each other hydrogen, C 1 -C 18 alkyl, C 3 -C 18 alkenyl, C 3 -C 18 alkinyl or phenyl which are unsubstituted or substituted by NO 2 , halogen, amino, hydroxy, cyano, carboxy, C 1 -C 4 alkoxy, C 1 -C 4 alkylthio, C 1 -C 4 alkylamino or di(C 1 -C 4 alkyl)amino; A is a group capable of forming a stable free nitroxyl radical A•, which is bound via its oxygen atom to the carbon atom; Y is O, NR 3 or CHR 3 —X a , wherein X a is O, S or NR 3 ; R 3 is hydrogen, C 1 -C 18 alkyl, C 3 -C 18 alkenyl, C 3 -C 18 alkinyl or phenyl which are unsubstituted or substituted by NO 2 , halogen, amino, hydroxy, cyano, carboxy, C 1 -C 4 alkoxy, C 1 -C 4 alkylthio, C 1 -C 4 alkylamino or di(C 1 -C 4 alkyl)amino; Q 1 is an organic radical derived from an unsubstituted or substituted triazine, from a polycarboxylic acid or polycarboxylic acid derivative having 2-6 carboxylgroups, from a multifunctional alkylating agent having 2-6 functional groups or from a polyisocyanate having 2-6 isocyanate groups; Q 2 is an organic radical derived from a mono or polyfunctional alcohol, mono or polyfunctional aminoalcohol, mono or polyfunctional amine mono or polyfunctional mercaptane, mono or polyfunctional phenol or mono or polyfunctional thiophenol; and n is a number from 2 to 10; with the proviso, that in formula (I) if n is 2, R 1 is H and R 2 is —CH 2 —O-tert-butyl, A is not 2,2,6,6-tetramethylpiperidine or 2,2,6,6-tetramethylpiperidine-4-carboxylic acid.