The use of benzotriazole UV absorbers of formula ##STR00001## wherein A
is a radical of formula ##STR00002## B is a radical of formula
##STR00003## ##STR00004## R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5
and R.sub.6 are each independently of the others hydrogen, C.sub.1
C.sub.16alkyl; C.sub.5 C.sub.7cycloalkyl; halogen;R.sub.9 is hydrogen,
C.sub.1 C.sub.12alkyl; or C.sub.5 C.sub.7cycloalkyl;R.sub.7, R.sub.8 and
R.sub.10 are each independently of the others hydrogen, C.sub.1
C.sub.12alkyl, C.sub.5 C.sub.7cycloalkyl, C.sub.1 C.sub.12hydroxyalkyl;X
is halogen; a radical of formula ##STR00005## ##STR00006## sulfate,
phosphate, lactate, citrate, tartrate; R.sub.11 is C.sub.1 C.sub.12alkyl;
or C.sub.5 C.sub.7cycloalkyl; R.sub.12 and R.sub.13 are each
independently of the other hydrogen; or C.sub.1 C.sub.5alkyl; x is from 0
to 10; and y is from 1 to 20; in the cosmetic treatment of human hair for
protection against UV radiation is described.
