Described is the use of benzotropolone and their derivatives, especially the compounds of formula (1); wherein R2, R3, R4, R5 and R6 independently of one another are hydrogen; OH; C1-C30alkyl, C2-C30al-kenyl, C1-C30alkoxy, C3-C12cycloalkyl or C1C30hydroxyalkyl, which may be substituted by one or more E and/or interrupted by one or more D; C6-C20aryl, which may be substituted by one or more G; C4-C20heteroaryl, which may be substituted by one or more G, C2-C18alkenyl, C2-C18alkynyl, C7-C25aralkyl, CN, or —CO—R17; C1-C30mono- or dialkylamino; COR9; COOR9; CONR9R10; CN; SO2R9; OCOOR9; OCOR9; NHCOOR9; NR9COR10; NH2; *—(CO)—NH—(CH2)n1—(PO)—(OR11)2; —(CO)—O—(CH2)n1—(PO)—(OR11)2; sulphate; sulphonate; phosphate; phosphonate; —(CH2)n2—[O—(SO2)]n3—OR11; —O—(CH2)n4(CO)n5—R11; —(O)n6—(CH2)n7—(PO)—(OR9)2; —(O)n6—(CH2)n7—SO2—OR9; halogen; organosilanyl; organo-siloxanyl; or a sugar residue linked directly in an α- or β-mode via the anomeric oxygen to the benzotropolone system or via a linear or branched alkylene, alkenylene, alkadiene or alkatriene spacer (sugar-(CH2)n—(X1)1 or 0-benzotropolone system, wherein n=1-10 and X1═—O—; —(CO)—; —O—CO—; —COO—, —NH—; —S—; —SO2—); R1, R7 and R8 independently of one another are hydrogen; C1C12alkyl or C3-C12-cycloalkyl, which may be substituted by one or more E and/or interrupted by one or more D; C6-C20aryl, which may be substituted by one or more G; C4-C20heteroaryl, which may be substituted by one or more G, C2-C18alkenyl, C2-C18alkynyl, C7-C25aralkyl, or COOR9; COR9; CONR9R10; SO3R9; SO2R9; PO3(R9)2; PO2(R9)2; organosilanyl; organosiloxanyl; or a sugar residue linked directly in an α- or β-mode via the anomeric oxygen to the benzotropolone system or via a linear or branched alkylene, alkenylene, alkadiene or alkatriene spacer (sugar-(CH2)n—(X2)1 or 0—*, wherein n=1-10 and X2═—C(═O)—; —O—CO—*); R9 and R10 independently from each other are hydrogen; C1C18alkyl or C3-C12-cycloalkyl which may be substituted by one or more E and/or interrupted by one or more D; C6-C20aryl, which may be substituted by one or more G; C4-C20heteroaryl, which may be substituted by one or more G; organosilanyl; organosiloxanyl; or a sugar residue linked directly in an α- or β-mode via the anomeric oxygen or via a linear or branched alkylene, alkenylene, alkadiene or alkatriene spacer (sugar-(CH2)n—*, wherein n=1-10); or R9 and R10 together form a five or six membered ring, R11 is hydrogen; or C1-C5alkyl; n1, n2, n4 and n7 independently from each other are a number from 1 to 5; n3, n5 and n6 independently from each other are a 0; or 1; D is —CO—; —COO—; —S—; —SO—; —SO2-; —O—; —NR14—; —S1R19R20—; —POR11—; —CR12═CR13—; or —C≡C—; and E is —OR18; —SR18; —NR14R15; —NR14COR15; —COR17; —COOR16; —CONR14R15; —CN; halogen; Or SO3R18; SO2R18; PO3(R18)2; PO2(R18)2; organosilanyl; organosiloxanyl; or a sugar residue linked directly in an α- or β-mode via the anomeric oxygen or via a linear or branched alkylene, alkenylene, alkadiene or alkatriene spacer (sugar-(CH2)n-(X1)1 or 0—*, wherein n=1-10 and X1=—O—; —C(═O)—; —O—CO—; —COO—; —NH—; —S—; —SO2—); G is E; C1-C18alkyl, which is optionally interrupted by D; C1-C18perfluoroalkyl; C1-C18alkoxy, which is optionally substituted by E and/or interrupted by D; wherein R12, R13, R14 and R15 independently of each other are hydrogen; C6-C18aryl which is optionally substituted by OH, C1-C18alkyl or C1-C18alkoxy; C1-C18alkyl, which is optionally interrupted by —O—; or Ri4 and Ri5 together form a five or six membered ring, Ri6 is hydrogen; C6-Ci8aryl which is optionally substituted by OH, C1-C18alkyl or d-C18alkoxy; C1-C18alkyl which is optionally interrupted by —O—; R17 is H; C6-C18aryl which is optionally substituted by OH, C1-C18alkyl or C1-C18alkoxy; or d-C18alkyl which is optionally interrupted by —O—; R18 is hydrogen; C6-C18aryl, which is optionally substituted by OH, C1-C18alkyl or d-C18alkoxy; C1-C18alkyl, which is optionally interrupted by —O—; R19 and R20 independently of each other are hydrogen; C1-C18alkyl; C6-C18aryl which is optionally substituted by C1-C18alkyl; and R21 is C1-C18alkyl; or C6-C18aryl, which is substituted by C1-C18alkyl; * means, that this radical is directed to the benzotropolone moiety; for the protection of human and animal hair and skin against UV radiation.