Use of HALS compounds

A compound of formula I ##STR19## in which R is CH.sub.3 ;

• each R.sub.1, independently, is --CH.sub.3 or --CH.sub.2 (C.sub.1-4 alkyl) or both groups R.sub.1 form a group --(CH.sub.2).sub.5 --;
• each R.sub.2, independently, is --CH.sub.3 or --CH.sub.2 (C.sub.1-4 alkyl) or both groups R.sub.2 form a group --(CH.sub.2).sub.5 --;
• R.sub.9 is hydrogen or methyl;
• R.sub.10 is methoxyphenyl;
• and
• A is --O--, --N(C.sub.1-4 alkyl)--, or --NH--.

A process for preparing a compound of formula I ##STR20## in which R is hydrogen, oxygen, --OH, C.sub.1-24 alkyl, --O--C.sub.1-24 alkyl, --O--CO--C.sub.1-24, --O--CO-phenyl, or --COR.sub.5 ;

• each R.sub.1, independently, is --CH.sub.3 or --CH.sub.2 (C.sub.1-4 alkyl), or both groups R.sub.1 form a group --(CH.sub.2).sub.5 ;
• each R.sub.2, independently, is --CH.sub.3 or --CH.sub.2 (C.sub.1-4 alkyl) or both groups R.sub.2 form a group --(CH.sub.2).sub.5 --;
• R.sub.3 is hydrogen or C.sub.1-4 alkyl;
• R.sub.5 is --C(R.sub.3).dbd.CH.sub.2, C.sub.1-6 alkyl, phenyl, CO--C.sub.1-24 alkyl, --CO-phenyl, --NR.sub.7 R.sub.8, --CH.sub.2 --C.sub.6 H.sub.5, --CO--OC.sub.1-12 alkyl, or --COOH;
• R.sub.7 is hydrogen, C.sub.1-12 alkyl, C.sub.5-6 cycloalkyl, phenyl, phenyl-C.sub.1-4 alkyl, or C.sub.1-12 alkylphenyl;
• R.sub.8 is C.sub.1-12 alkyl, or hydrogen;
• R.sub.9 is hydrogen or methyl;
• R.sub.10 is an aromatic single ring, an aromatic fused 2 or 3 ring group, or a group of the formula ##STR21## A is --O--, --N(C.sub.1-4 alkyl)--, or --NH-- comprising the process step of:
• condensing one of mole of a compound or a derivative thereof of the formula II
• R.sub.10 --CH.dbd.C.dbd.(COOH).sub.2 II
• with 2 moles of a compound of formula III ##STR22##