general formula i residues of glycerol trimethylolethane trimethylolpropane tris 2 hydroxyethyl isocyanurate pentaerythritol diglycerol ditrimethylolethane ditrimethylolpropane mannitol sorbitol dipentaerythritol and inositol may be cited as the piperidine compound of the present invention represented by the above general formula i those wherein the polyhydric alcohol residue represented by a is a group having a neopentyl structure represented by the following formula are particularly preferable because of the large effects thereof str3 wherein r represents an alkyl group having 1 to 18 carbon atoms or ch 2 and a is 0 or 1 as examples of the alkyl groups represented by r 1 and r 2 in the above general formula i unsubstituted alkyl groups such as methyl ethyl propyl isopropyl butyl isobutyl pentyl hexyl octyl 2 ethylhexyl decyl dodecyl tridecyl tetradecyl and octadecyl groups and substituted alkyl groups such as benzyl phenylethyl 2 hydroxyethyl 2 3 epoxypropyl dimethylaminopropyl and methoxyethyl groups may be cited as examples of the alkoxy group represented by r 1 alkoxy groups derived from the above mentioned alkyl groups may be cited as examples of the acyl group represented by r 1 acetyl propionyl acryloyl methacryloyl butyroyl and octanoyl groups may be cited as example of the alkylene group represented.