Patent ID: 8221729

Claim:
A method for protecting human and animal hair and skin from harmful effects of UV radiation wherein said method comprises applying to said hair and said skin an effective amount of 2-(2′-Hydroxy-4′-aminophenyl)benzotriazole derivatives of formula wherein R 1 and R 4 independently of each other are hydrogen; C 1 -C 28 alkyl; C 1 -C 28 alkoxy; C 2 -C 28 alkenyl; C 2 -C 28 alkinyl; C 3 -C 12 cycloalkyl; C 3 -C 12 cycloalkenyl; C 7 -C 28 aralkyl; C 1 -C 20 heteroalkyl; C 3 -C 12 cycloheteroalkyl; or C 5 -C 16 heteroaralkyl; and wherein C 1 -C 28 alkyl, C 1 -C 28 alkoxy, C 2 -C 28 alkenyl and C 2 -C 28 alkinyl are unsubstituted or may be substituted by at least one C 1 -C 5 alkyl, C 1 -C 5 alkoxy or hydroxy; R 2 and R 3 independently of each other are hydrogen; C 1 -C 28 alkyl; C 2 -C 28 alkenyl; C 2 -C 22 alkinyl; C 3 -C 12 cycloalkyl; C 3 -C 12 cycloalkenyl; C 7 -C 28 aralkyl; C 1 -C 20 heteroalkyl; C 3 -C 12 cycloheteroalkyl; C 5 -C 16 heteroaralkyl; and wherein C 1 -C 28 alkyl, C 1 -C 28 alkoxy, C 2 -C 28 alkenyl and C 2 -C 28 alkinyl are unsubstituted or may be substituted by at least one C 1 -C 5 alkyl, C 1 -C 5 alkoxy or hydroxy; or CO—R 5 ; or R 2 and R 3 together with the linking nitrogen form a 5- to 7-membered, monocyclic, carbocyclic or heterocyclic ring; R 5 is C 1 -C 28 alkyl; C 2 -C 28 alkenyl; C 2 -C 28 alkinyl; C 3 -C 12 cycloalkyl; C 3 -C 12 cycloalkenyl; C 7 -C 20 aralkyl; C 1 -C 20 heteroalkyl; C 3 -C 12 cycloheteroalkyl; C 1 -C 5 alkoxycarbonyl-C 1 -C 5 alkyl; or C 5 -C 16 heteroaralkyl; and n is 1, 2, 3 or 4.