| 摘要 |
<p>Hair colouring compositions are provided which comprise (i) one or more developers selected from amino aromatic systems capable of being oxidised and thereafter undergoing a single electrophilic attack, and (ii) one or more couplers selected from (A) phenols and naphthols having an active leaving group in the para position relative to the hydroxyl group, (B) 1,3-diketones containing the group (a) in which Z is an active leaving group, and (C) compounds containing the group (b) in which Z is an active leaving group, and X is an active leaving group or a non-leaving substituent, such that in the presence of an oxidising agent the or each developer reacts with the or each coupler substantially only at the positions having the active leaving group Z and, if X is an active leaving group, X, and (iii) an antioxidant. Use of an antioxidant with these colouring agents gives good fade resistance. A kit, method and system for colouring hair are also provided using these colouring agents.</p> |
