Abstract: A photostable UV absorbent with maximum absorption above 340 nm having the formula: ##STR1## wherein R is --CO(R.sub.2) or phenyl optionally substituted with lower alkyl and/or lower alkoxy;R.sub.2 is --alkyl, --O(C.sub.2+ alkyl), ##STR2## n has a value of from 2 to 8; S and T each independently are hydroxy, lower alkyl, lower alkoxy or, when R.sub.2 is alkyl or alkoxy, S can also be phenyl and when R.sub.2 is alkoxy, T is alkoxy, or S+T taken with the phenyl ring form a naphthyl radical or a fused benzodioxol-5-yl heterocyclic radical;k+l has a value of from 0 to 3 with the proviso that, when R.sub.2 is--O(alkyl), T is --O(lower alkyl) and the value of l is 2 or 3;R.sub.3 is hydrogen or lower alkylene;R.sub.4, R.sub.5, and R.sub.6 are each independently C.sub.1 to C.sub.18 alkyl or one of R.sub.4, R.sub.5 and R.sub.6 can be phenyl andA is an anion.