Urea derivatives, their preparation, and their use as light stabilizers

Claim 1

A compound of the formula (I) ##STR3## in which R 1 and R 2 , being identical or different, each are linear or branched alkyl having from 1 to 12 carbon atoms, or R 1 and R 2 together with the carbon atom to which they are linked form a cyclopentane or cyclohexane ring which may also be methyl-substituted or a 2,2,6,6-tetramethylpiperidine ring the carbon atom 4 of which is identical with the carbon atom 7 of the spirodecane system; R 3 is hydrogen, alkyl or isoalkyl having from 1 to 30 carbon atoms, or phenylalkyl having from 7 to 10 carbon atoms, the aliphatic chain having from 1 to 4 carbon atoms; R 4 is hydrogen, alkyl having from 1 to 30 carbon atoms, phenyl or naphthyl, which may be substituted by a halogen atom, or alkyl radical having from 1 to 4 carbon atoms, or phenylalkyl having from 7 to 10 carbon atoms, the aliphatic chain containing from 1 to 4 of the latter carbon atoms; or R 3 and R 4 together with the carbon atom linking them form a cycloalkane ring having from 4 to 20 carbon atoms; R 5 , when n is 1, is alkyl having from 1 to 20 carbon atoms, alkenyl having from 3 to 18 carbon atoms, cycloalkyl having from 5 to 12 carbon atoms, which may be substituted by C 1 -C 4 -alkyl phenyl or naphthyl which may be substituted by a chlorine atom or alkyl having from 1 to 18 carbon atoms, or phenylalkyl having from 7 to 18 carbon atoms, the aryl ring containing 6 carbon atoms; R 5 , when n is 2, is linear or branched alkylene having from 2 to 20 carbon atoms, phenylene or naphthylene which may be substituted by C 1 -C 4 -alkyl, or phenylalkylene having from 7 to 18 carbon atoms; and R 6 is hydrogen, oxygen, hydroxyl or alkyl having from 1 to 4 carbon atoms.