Patent ID: 11964037
Assignee: KAO CORPORATION
Field: Pharmaceuticals (Chemistry)
Classification: CPC A | IPC A

Claim 0:
1. A hair dyeing method, comprising the following in order:
Step 1: applying on hair a hair dye composition (I) comprising (A) a compound represented by the following general formula (1A) or a salt thereof and (B) an organic alkaline agent and having a pH of 9.0 or more and 11.0 or less:, wherein a broken line represents the presence or absence of a π bond; R1 represents a hydroxy group or an acetoxy group; and R2 represents a hydrogen atom, an acetyl group, a methyl group, or an ethyl group; and
Step 2: applying on the hair a hair treatment agent (II) comprising (C) an organic acid or a salt thereof and having a pH of 5.5 or less,
wherein after performing the step 1, the hair is subjected to the step 2 while maintaining in a wet state in which an amount of water per gram of the hair is 0.008 g or more.