Colorant of formula (I): wherein A signifies a monovalent organic residue comprising a chromophore group; B signifies a bivalent organic residue selected from the class consisting of aromatic, heteroaromatic, cycloaliphatic and aliphatic groups containing from 2 to 10 carbon atoms, optionally substituted; and C signifies the residue of compound comprising at least one amido group, one primary amino group, and one secondary amino group, wherein C is linked to B via a nitrogen atom of an amino group, wherein said compound is a poly(amidoamine).