The invention relates to unsaturated fatty hydroxy acid derivatives of formula (I), wherein Rn is independent from each other H or linear or branched alkyl group which contain from 1 to 6 carbon atoms and which are possibly substituted by a halogen atom, in particular a fluorine atom, RI is H, F, Cl, Br or CF3, R is H or linear or branched alkyl group which contain from 1 to 6 carbon atoms and which are possibly substituted by a halogen atom, in particular a fluorine atom and 3=n=14. Said derivatives is suitable for producing an anti-radical, anti-inflammatory and antipruritic dermocosmetologic composition and/or for treating keratinisation and pigmentation troubles and/or for improving healing.
