Substituted quinones or analogues as colouring agents

A compound of the formula I

• where
• E denotes NR4 or O,
• Sp denotes a bond, alk, —C(O)— or —(CO)-alk,
• D denotes a colour chromophore,
• R1, R2 or R3 each, independently of one another, denote —H, -A, —OA-, —(CH2)p—OH, —C(O)OA, COOH or COOX,
• p denotes an integer from 1 to 4,
• X is the counterion to the [COO−] group,
• R4 denotes A,
• alk denotes a linear or branched or cyclic alkylene group having 1 to 18 C atoms and
• A denotes a linear or branched alkyl group having 1 to 20 C atoms and/or salts, tautomers, stereoisomers and/or solvates thereof, including mixtures thereof in all ratios.