Abstract: Provided is a hair dye composition comprising a direct dye (1): A—CR1═N—NR2—B X−  (1) [wherein, A represents a group (2) or (3): (in which, R3, R4 and R5 each independently represents a (substituted) C1-6 alkyl group, ring C may have a substituent or may by cyclocondensed with an aromatic ring, R6 and R7 each independently represents a (substituted) C1-6 alkyl group, or may be coupled to form a heterocycle together with the adjacent nitrogen atom, Z represents a (substituted) C1-4 divalent linear hydrocarbon group and ring D may be cyclocondensed with an aromatic ring), B represents a (substituted) aromatic group, R1 represents H or a (substituted) C1-6 alkyl group, R2 represents H or a (substituted) C1-6 alkyl group or a (substituted) aromatic group or may form a heterocycle together with the C atom of the aromatic ring B, and X− represents an anion].

Abstract: Provided is a hair dye composition containing a direct dye (1). This hair dye composition has markedly high hair dyeing power, has less color fade over time and undergoes a small change in the color tone of the dye even after storage. wherein, R1 to R4 each represents a (substituted) C1-6 alkyl group, (substituted) alkenyl group or (substituted) aryl group or R3 and R4, when taken together with the adjacent C, form a 5 to 12 membered ring, R5 represents H, (substituted) C1-6 alkyl group, (substituted) alkenyl group, (substituted) aryl group or acyl group, X1 and X2 each represents H or halogen atom, Y1 and Y2 each represents H, (substituted) C1-6 alkyl group, (substituted) alkenyl group, (substituted) C1-6 alkoxy group or halogen atom, Z1 and Z2 each represents H, (substituted) C1-6 alkyl group, (substituted) alkenyl group, (substituted) C1-6 alkoxy group, nitro group or halogen atom, and A− represents an anion.

Abstract: Provided is a hair dye composition comprising a direct dye (1): A—CR1═N—NR2—B X−  (1) [wherein, A represents a group (2) or (3): (in which, R3, R4 and R5 each independently represents a (substituted) C1-6 alkyl group, ring C may have a substituent or may by cyclocondensed with an aromatic ring, R6 and R7 each independently represents a (substituted) C1-6 alkyl group, or may be coupled to form a heterocycle together with the adjacent nitrogen atom, Z represents a (substituted) C1-4 divalent linear hydrocarbon group and ring D may be cyclocondensed with an aromatic ring), B represents a (substituted) aromatic group, R1 represents H or a (substituted) C1-6 alkyl group, R2 represents H or a (substituted) C1-6 alkyl group or a (substituted) aromatic group or may form a heterocycle together with the C atom of the aromatic ring B, and X− represents an anion].

Abstract: Provided is a hair dye composition comprising a direct dye (1):

Abstract: Provided is a hair dye composition containing a direct dye (1). This hair dye composition has markedly high hair dyeing power, has less color fade over time and undergoes a small change in the color tone of the dye after storage. wherein, ring A may represents a benzene ring which may have a substituent or the like, B represents an aryl or heterocyclic group, D represents N or CR4 (wherein R4 represents H or alkyl), E represents NR5, CR6R7 or CR6═CR7 (wherein R5 represents alkyl or the like, and R6 and R7 each represents H or alkyl) or, O or S, R1 represents alkyl or the like, and n stands for 0 or 1, with the proviso that at n=0, R2 and R5 form, when taken together with N—C—C, a heterocycle, or R2 is bonded to B, thereby forming a heterocycle and at n=1, R2 and R3 form, when taken together with C═D—N, a heterocycle, and X− represents an anion.

Abstract: Provided is a hair dye composition containing a direct dye A—D═D—B. This hair dye composition has markedly high hair dyeing power, has less color fade over time and undergoes a small change in the color tone of the dye even after storage. A represents any one of the following groups (2) to (8): (in which R1, R4, R5 and R6 each represents H, (substituted) C1-6 alkyl group, etc., R2 and R3 each represents (substituted) C1-6 alkyl group, etc., or form, when taken together with the adjacent C, a cycloalkane ring, Q represents N or group CR′, R7 represents (substituted) aralkyl group or a group CH2—CH(OH)—CH2—OR″, R8 and R9 each represents H, (substituted) C1-6 alkyl, etc., or form, when taken together with the adjacent N, a heterocycle, X− represents an anion, and rings C-I may each have a further substituent or a condensed ring), D represents N or group CR′″, and B represents the residue of a coupling component.

Abstract: Provided is a hair dye composition comprising as a direct dye a compound represented by the following formula (1), (2), (3) or (4): [wherein, R1 and R1′ each independently represents a (substituted) C1-6 alkyl or a (substituted) aryl group; W and W′ each independently represents a group —A—NR2R3 or a (substituted) heterocyclic aromatic group; A and A′ each independently represents a divalent (substituted) aryl group; R2, R2′ and R3 each independently represents H, a (substituted) alkyl or a (substituted) aryl group, or R2, R2′ or R3 may be bonded to A or A′, thereby forming a heterocycle, R2 and R3, or R2 and R2′ are coupled to form a heterocycle, together with the adjacent atom; R4 to R6 each independently represents H, (substituted) alkyl or (substituted) alkenyl group; Q represents a divalent organic group; X represents a modified carboxy group, an —SO2—T— group (in which, T represents an alkyl, alkenyl or aryl)

Abstract: The present invention provides a treatment composition for dyed hair which effectively prevents color fading of the dyed hair, to thereby maintain the color of the dyed hair for prolonged periods. The composition contains the following components (A), (B), and (C): (A) an organic solvent selected from among aromatic alcohols, lower alkylene carbonates, N-alkylpyrrolidones, and formamides; (B) an organic carboxylic acid or a salt thereof; and (C) a lower alcohol, a polyhydric alcohol, or a lower alkyl ether of a polyhydric alcohol; wherein the pH of the composition falls within the range of 1-6 inclusive, and the composition does not contain any dye. In use, the composition is applied to hair dyed with an acid-dye-type hair dye composition; and then the hair is left to stand for 5-30 minutes at 20-60° C., followed by washing.

Abstract: A hair dye composition containing a direct dye (1) wherein, R1, R2 represents H or a lower alkyl group, A represents a group (2) or (3) and wherein B represents a group —Z1, —NR8—Z1 or —CH=Z2.

Abstract: Provided is a hair dye composition containing a direct dye (1). This hair dye composition has markedly high hair dyeing power, has less color fade over time and undergoes a small change in the color tone of the dye even after storage. wherein, rings A and B represents a benzene ring which may have a substituent and may further be cyclocondensed with another aromatic ring, D and E each independently represents a group NR3 (in which R3 represents a C1-6 alkyl group) or an S atom, R1 and R2 each independently represents a C1-6 alkyl group, and X− represents an anion.

Abstract: Provided is a hair dye composition containing a direct dye (1). This hair dye composition has markedly high hair dyeing power, has less color fade over time and undergoes a small change in the color tone of the dye after storage.

Abstract: Provided is a hair dye composition containing a direct dye A−D=D−B. This hair dye composition has markedly high hair dyeing power, has less color fade over time and undergoes a small change in the color tone of the dye even after storage.

Abstract: Provided is a hair dye composition containing a direct dye (1). This hair dye composition has markedly high hair dyeing power, has less color fade over time and undergoes a small change in the color tone of the dye even after storage.

Abstract: Provided is a hair dye composition containing a direct dye (1). This hair dye composition has markedly high hair dyeing power, has less color fade over time and undergoes a small change in the color tone of the dye even after storage.

Abstract: Provided is a hair dye composition comprising a direct dye (1):

Abstract: Provided is a hair dye composition comprising as a direct dye a compound represented by the following formula (1), (2), (3) or (4): 1

Abstract: The present invention provides a treatment composition for dyed hair which effectively prevents color fading of the dyed hair, to thereby maintain the color of the dyed hair for prolonged periods.