| abstract |
(57) Abstract: [PROBLEMS] To provide a hair treatment agent which has excellent moisturizing properties and conditioning effects on hair, gives a natural finish, and reduces damage to the hair during perming. SOLUTION: A polyaspartic acid derivative having the following unit structures (A), (B) and (C) and a hair treatment composition containing the same. Embedded image (In the formula, R 1 represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and p represents an integer of 1 to 4.) [In the formula, R 2 represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, and Y is (Wherein R 3 to R 4 represent an alkyl group having 1 to 4 carbon atoms, Z represents an anion derived from an organic acid or an inorganic acid), and q represents an integer of 2 to 6. ] (In the formula, M represents a hydrogen atom, an alkali metal, an organic amine or a basic amino acid.) |