The invention provides novel nitro-paraphenylenediamine derivatives of the formula: ##STR1## in which R.sub.1 denotes an alkyl group, a monohydroxy- or polyhydroxy-alkyl group or an aminoalkyl group, the amino group of which is optionally monosubstituted or disubstituted by an alkyl group, and R.sub.2 denotes an alkyl group, or a cosmetically acceptable salt thereof. These derivatives are useful as direct dyes, especially for dyeing human hair.
该发明提供了公式为:##STR1##的新型硝基
对苯二胺衍
生物,其中R.sub.1代表烷基,单羟基或多羟基烷基或
氨基烷基,其
氨基可能被烷基单取代或双取代,R.sub.2代表烷基,或其在化妆品中可接受的盐。这些衍
生物可作为
直接染料使用,特别适用于染发。