The s-triazines of formula I are UV absorbers having high thermal stability and surprisingly high extinction coefficients making them of especial value for stabilizing polymer subsnates, especially automotive coatings. Tris-aryl-s-triazines in which at least one of the aryl groups has an hydroxy group ortho to the point of attachment to the triazine ring are well known UV absorbers. It is also well-known that this class of triszines protect organic polymers from the deleterious effects of exposure to actinic radiation. The instant invention pertains to novel dimetic or oligomeric tris-aryl-s-triazines wherein at least one of the aryl groups is a biphenylyl or substituted biphenylyl moiety. More particularly, the instant invention relates to compounds of formula I ##STR1## wherein G.sub.1, G.sub.2, and E.sub.2 are here-in-below defined.