| 摘要 |
PURPOSE:A hair dye that contains, as an active ingredient, a naphthalene derivative, thus developing dyeing power meeting practical use at a temperature lower than 40 deg.C with a low concentration without injury to hair and irritation to scalp skins and storage stability. CONSTITUTION:The objective dye contains a naphthalene derivative of the formula. The amount of the compound is more than 0.05wt%, preferably more than 0.1wt% and less than 2wt%. The naphthalene derivative of the formula is novel and synthesized by reducing a corresponding 2-benzylamino-5,8- dihydroxynaphthoquinone with a reducing agent such as sodium ditionate in the presence of an alkali such as potassium hydroxide, sodium hydroxide or sodium carbonate in water, alcohol or their mixture, or with zinc dust in hydrochloric acid. The color of dyeing hair is reddish brown to brown. |
