Patent ID: 7060108

Claim:
A hair dying process comprising: applying to the hair an oxidizing-agent-free, air oxidative, one-pack hair dye composition, which consists essentially of an oxidation catalyst of two components (a 1 ) and (a 2 ) wherein (a 1 ) a water-soluble hydrochloride, sulfate, nitrate, carbonate, hydrogencarbonate, phosphate or organic acid salt of iron in an amount of 0.001 to 10 wt % in terms of the anhydrous form of the salt, based on the whole composition, and (a 2 ) a chelating agent selected from the group consisting of ethylenediaminetetraacetic acid, hydroxyethylethylenediaminetriacetic acid, ethylenediaminedisuccinic acid and salts thereof in an amount of 0.001 to 10 wt % based on the whole composition; (b) a color-developing substance in an amount of 0.01 to 10 wt % based on the whole composition, to hair without mixing said hair dye composition with an oxidizing agent; and (c) water; and after allowing the hair to undergo treatment for 5 minutes to 1 hour, rinsing the applied hair dye composition from the hair with water.