The present invention relates to a para-aminophenol compound of formula (I), the addition salts thereof with an acid and the solvates thereof:in which: R represents a hydrogen or halogen atom a C1-C4 alkyl radical a carboxyl radical or a (C1-C4)alkoxycarbonyl radicalZ1 is an oxygen atom or a group NR2R2 is a hydrogen atom or a linear or branched C1-C4 alkyl radical, a benzyl radical or an acetyl radicalR1 is a saturated, linear or branched C1-C10 alkyl radical, which is substituted with or interrupted by a cationic radical, optionally interrupted by one or more oxygen atoms and/or by one or more groups NR2, optionally substituted with one or more radicals chosen from hydroxyl, alkoxy or C1-C4 hydroxyalkyl radicals or R1 is a saturated, unsaturated or aromatic cationic 5- to 8-membered heterocycle optionally substituted with one or more radicals chosen from C1-C4 alkyl, hydroxyl, C1-C4 alkoxy, amino, (C1-C4)alkylamino, di(C1-C4)alkylamino, thio, (C1-C4)alkylthio, carboxyl, (C1-C4)alkylcarbonyl, sulfonyl, amido or C1-C4 hydroxyalkyl radicals and when Z1 represents NR2 then R1 and R2 may form, together with the nitrogen atom to which they are attached, a saturated or unsaturated cationic 5- to 8-membered heterocycle optionally substituted with one or more radicals chosen from C1-C10 alkyl radicals and hydroxyl, C1-C4 alkoxy, amino, (C1-C4)alkylamino, di(C1-C4)alkylamino, thio, (C1-C4)alkylthio, carboxyl, (C1-C4)alkylcarbonyl, sulfonyl, amido and C1-C4 hydroxyalkyl radicals, it being possible for this heterocycle to contain one or more heteroatoms chosen from N or O, preferably N orR1 and R2 may form, together with the nitrogen atom to which they are attached, a saturated or unsaturated noncationic 5- to 8-membered heterocycle substituted with a cationic radical and optionally substituted with one or more radicals chosen from C1-C10 alkyl radicals and hydroxyl, C1-C4 alkoxy, amino, (C1-C4)alkylamino,
