Agents for dyeing keratin fibres, containing at least one dimeric, dicationic azo dye with special substitution pattern

An agent for changing the colour of keratinic fibers, the agent comprising, in a cosmetic support, (a) at least one direct dye with formula (I),

• wherein
• one of Het1 and Het2 represents one of the structures (II), (III), (IV), (V), (VI) or (VII), and
• the other of Het1 and Het2 represents one of the structures (III), (V), (VI) or (VII),
• R1, R3 independently of each other represent a C1-C6 alkyl group or a C1-C6 alkoxy group,
• R2, R4 each represent a hydrogen atom,
• R5, R6 independently of each other represent a hydrogen atom, a C1-C6 alkyl group or a C2-C6 alkenyl group,
• Q represents a group with formula (VIII),
• * —(CH2)n-* (VIII)
• n represents a whole number from 3 to 6,
• R7, R10 each independently of each other represent a C1-C6 alkyl group or a C2-C6 alkenyl group,
• R8, R9 each independently of each other represent a hydrogen atom, a C1-C6 alkyl group, a halogen atom from the group chlorine, bromine, fluorine or iodine, a C1-C6 alkoxy group or a nitro group, and
• X represents a physiologically acceptable anion selected from the group consisting of chloride, bromide, iodide, methyl sulphate, methyl sulphonate, p-toluenesulphonate, acetate, hydrogen sulphate, ½ sulphate or ½ tetrachlorozincate.