| 摘要 |
PURPOSE:To obtain a hair dye composition having excellent dyeing property, soluble in water, usable in various forms and wide pH range, easily formable to a preparation, having high stability and safety and useful as a hair dye, by using specific indole-2-carboxylic acid derivatives as active component. CONSTITUTION:The objective composition contains an indole-2-carboxylic acid derivative of formula (one of R<1> and R<2> is H and the other is H, OH or 1-20C alkyl; R<3> is H, CH3, OCH3 or benzoxycarbonyl; dotted line represents the presence or absence of single bond), e.g., 5,6-dihydroxyindole-2-carbocylic acid or its water-soluble salt as an active component. The composition is used in the dyeing of hair by contacting with hair treated with a pretreatment agent containing one or more kinds of transition metal salts. The amount of the compound of formula to be compounded to the hair dye composition is preferably 0.01-10wt.% and a hair dye is prepared by adding a stabilizer, an oxidizing agent, a permeation promoter, etc. |
