2,2,6,6-tetraalkyl-piperidine compounds useful as light stabilizers

A lacquer composition based on a member selected from the group consistency of acrylic resins, alkyd resins, polyester resins and acrylic resins, alkyd resins and polyester resins crosslinked with melamine/formaldehyde resins, epoxide resins or polyisocyanates, which contains at least one 4-oxalamido-2,2,6,6-tetraalkylpiperidine compound of formula I ##STR43## in which R is hydrogen, oxygen, C.sub.1-8 alkyl or --CO--R.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.4 is an amide-forming group;
• R.sub.5 is --C(R.sub.10).dbd.CH.sub.2, C.sub.1-6 alkyl, phenyl, --CO--O--C.sub.1-4 alkyl or --NR.sub.7 R.sub.8 ;
• 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;
• and
• R.sub.10 is hydrogen or C.sub.1-4 alkyl.

A compound of formula I ##STR59## in which R is hydrogen, oxygen, C.sub.1-8 alkyl or --CO--R.sub.5, where R.sub.5 is --C(R.sub.10).dbd.CH.sub.2, C.sub.1-6 alkyl, phenyl --CO--O--C.sub.1-4 alkyl or --NR.sub.7 R.sub.8 and where 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 and R.sub.8 is C.sub.1-12 alkyl or hydrogen;

• 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.10 is hydrogen or C.sub.1-4 alkyl;
• and
• R.sub.4 is an amide-forming group
• with the proviso that when R is hydrogen, then R.sub.4 is not
• (i) N unsubstituted 2,2,6,6-tetraalkylpiperidine 4-amino;
• or
• (ii) unsubstituted phenylamino.