Xanthene dyes

A method of dyeing keratin-containing fibers comprising treating the fiber with at least one compound of formula (1) Y1—Z1—X1—S—S—X2—Z2—Y2,

• wherein
• X1 and X2 independently from each other are C1-C30alkylene, which may be interrupted by —NH, —O— or —S—;
• C2-C30alkenylene;
• C5-C30cycloalkylene;
• C5-C30arylene;
• or C5-C40arylene-C1-C30alkylene;
• or combinations thereof;
• Z1 and Z2 independently from each other are —C(O)—;
• —C(O)O—;
• —OCO—;
• —NR16—;
• (R16)NC(O);
• —O—;
• —S—;
• —S(O)—;
• C(O)—N—R16;
• or —S(O)2—;
• Y1 and Y2, independently from each other are the residue of an organic dye which corresponds to the formula
• R1 is N+R8R9;
• R8 and/or R9 independently from each other are hydrogen;
• C1-C12alkyl;
• or phenyl-C1-C4alkyl;
• or
• R8 and/or R9 are a bivalent C3-C6alkylene radical which is linked to the carbon atoms C1 or C2 respectively and, together with the linking nitrogen atom form a 6 to 16-membered carbocyclic ring;
• R2 is NR10R11;
• or OR10;
• R10 and R11, independently from each other are hydrogen;
• C1-C12alkyl;
• or phenyl-C1-C4alkyl;
• or
• R10 and/or R11 are a bivalent C3-C6alkylene radical which is linked to the carbon atoms C3 or C4 respectively and, together with the linking nitrogen or oxygen atom form a 6 to 16-membered carbocyclic ring;
• or
• R10 and R11 together with the linking nitrogen atom form a 4 to 8 membered carbocyclic ring;
• R3, R4, R5, R6 and R7 independently form each other are hydrogen;
• C1-C12alkyl;
• halogen;
• NR12R13;
• or a radical of formula (1a1)
• R12 and R13 independently from each other are hydrogen;
• C1-C12alkyl;
• phenyl-C1-C4alkyl;
• or a radical of formula (1a2)
• V is —O—;
• or —NR15;
• R14, R15 R16 and R17 independently from each other are hydrogen;
• or C1-C5alkyl;
• and
• Hal is a halogen atom;
• and wherein at least one of R3, R4, R5, R6 and R7 is hydrogen.

A composition comprising at least one compound of formula (1) Y1—Z1—X1—S—S—X2—Z2—Y2,

• wherein
• X1 and X2 independently from each other are C1-C30alkylene, which may be interrupted by —NH, —O— or —S—;
• C2-C30alkenylene;
• C5-C30cycloalkylene;
• C5-C30arylene;
• or C5-C40arylene-C1-C30alkylene;
• or combinations thereof;
• Z1 and Z2 independently from each other are —C(O)—;
• —C(O)O—;
• —OCO—;
• —NR16—;
• (R16)NC(O);
• —O—;
• —S—;
• —S(O)—;
• C(O)—N—R16;
• or —S(O)2—;
• Y1 and Y2, independently from each other are the residue of an organic dye which corresponds to the formula
• R1 is N+R8R9;
• R8 and/or R9 independently from each other are hydrogen;
• C1-C12alkyl;
• or phenyl-C1-C4alkyl;
• or
• R8 and/or R9 are a bivalent C3-C6alkylene radical which is linked to the carbon atoms C1 or C2 respectively and, together with the linking nitrogen atom form a 6 to 16-membered carbocyclic ring;
• R2 is NR10R11;
• or OR10;
• R10 and R11, independently from each other are hydrogen;
• C1-C12alkyl;
• or phenyl-C1-C4alkyl;
• or
• R10 and/or R11 are a bivalent C3-C6alkylene radical which is linked to the carbon atoms C3 or C4 respectively and, together with the linking nitrogen or oxygen atom form a 6 to 16-membered carbocyclic ring;
• or
• R10 and R11 together with the linking nitrogen atom form a 4 to 8 membered carbocyclic ring;
• R3, R4, R5, R6 and R7 independently form each other are hydrogen;
• C1-C12alkyl;
• halogen;
• NR12R13;
• or a radical of formula (1a1)
• R12 and R13 independently from each other are hydrogen;
• C1-C12alkyl;
• phenyl-C1-C4alkyl;
• or a radical of formula (1a2)
• V is —O—;
• or —NR15;
• R14, R15 R16 and R17 independently from each other are hydrogen;
• or C1-C5alkyl;
• and
• Hal is a halogen atom;
• and wherein at least one of R3, R4, R5, R6 and R7 is hydrogen.