| abstract |
(57) [Problem] To provide an air oxidation type hair dye excellent in dyeing power. SOLUTION: (A) 5,6-dihydroxyindoline-2-carboxylic acid or a salt thereof, (B) an alkali agent selected from sodium hydroxide, potassium hydroxide, ammonia, guanidine, basic amino acid and carbonate, and (C) 10-50% by weight A one-part air oxidation type hair dye composition containing a water-compatible organic solvent of the above, substantially not containing an alkanolamine, and having a pH of 8 to 12. |