Coloring agents and methods of use thereof

1. A functionalized dye comprising at least one chromophore and a color fastness moiety, wherein the chromophore is bound to the color fastness moiety by a linker, wherein said dye is a compound of formula Ia:

C-L-F  (Ia), wherein

C is a chromophore of formula IIg:

or

C is a chromophore represented by the following structural formula:

wherein

R 7c is attached to linker L;

R 7a , R 7b , R 7d , R 7e , R 7f , R 7g , R 7h , R 7i and R 7j are each independently hydrogen, hydroxyl, alkyl, alkenyl, alkynyl, aryl, amino, alkylammonium, sulfonyl, carbonyl, carboxy, alkoxy, aryloxy, halogen, acyl, oximyl, hydrazinyl, —NO 2 , —CN, a heterocyclic moiety or thioether;

R 26a is attached to linker L;

L is a linker of formula (III):

wherein

L covalently links the chromophore C via the left hand side of formula III to the color fastness moiety F via the right hand side of formula III;

a, b, c, d, e, and f are each independently an integer from 0-2, provided that at least one of a, b, c, d, e and f is not 0;

R 40 , R 41 , R 42 , R 43 , R 44 , R 45 , R 46 , R 47 , R 48 , R 49 , R 50 and R 51 are each independently absent or hydrogen;

E is NR 52 or NR 53 C═O;

R 52 and R 53 are each independently hydrogen or alkyl;

F is a color fastness moiety of formula (Va):

wherein

m, n, o, p, q and r are each independently an integer from 0-2, provided that at least one of m, n, o, p, q and r is not 0;

R 78 , R 79 , R 80 , R 81 , R 82 , R 83 , R 84 , R 85 , R 87 , R 88 and R 89 are each independently hydrogen or absent;

R 86 is absent, hydrogen or hydroxyl;

K is NR 90 , C(═O)NR 92 or OC═O;

W is NR 95 R 96 , CR 97 R 98 R 99 or OR 100 ;

R 90 and R 92 are each independently hydrogen or alkyl;

R 95 is alkyl and R 96 is hydrogen or alkyl, or R 95 and R 96 , together with the nitrogen to which they are attached are linked to form a 4-8-membered heterocyclic ring comprising 1-3 heteroatoms;

R 97 , R 98 and R 99 are hydrogen, hydroxyl, alkyl, alkoxy or heteroaryl; and

R 100 is hydrogen or alkyl;

or a cosmetically acceptable salt thereof.

2. The dye of claim 1 , wherein

C is a chromophore of formula IIg:

L is a linker of formula (III):

and

F is a color fastness moiety of formula (Va)

wherein

R 7a , R 7b , R 7d , R 7e , R 7f , R 7g and R 7i are each hydrogen;

R 7h is —NO 2 ;

R 7j is halogen;

R 7c is attached to L;

a, b, c, d and e are each 0;

E is NR 52 ;

R 52 is alkyl;

f is 1;

R 50 and R 51 are each hydrogen;

m, n and o are each 0;

K is C(═O)NR 92 ;

p, q and r are each 1;

R 84 , R 85 , R 87 , R 88 , R 89 and R 92 are each hydrogen;

R 86 is hydrogen or hydroxyl;

W is NR 95 R 96 , CR 97 R 98 R 99 , or OR 100

R 95 and R 96 are each alkyl or linked to form a ring;

R 97 is hydrogen;

R 98 is hydrogen or alkoxy;

R 99 is alkoxy or hydroxyl; and

R 100 is hydrogen;

or a cosmetically acceptable salt thereof.

3. The dye of claim 2 , wherein R 84 , R 85 , R 86 , R 87 , R 88 , R 89 and R 92 are each hydrogen; W is CR 97 R 98 R 99 ; R 97 and R 98 are each hydrogen; and R 99 is hydroxyl.

4. A dye composition comprising at least one dye of claim 1 and a medium suitable for dyeing keratin fibers.

5. A method for coloring hair comprising applying to said hair a dye composition comprising at least one dye of claim 1 , such that said hair is colored.

6. A kit comprising a dye composition comprising at least one dye of claim 1 and instructions for use.

7. A method for coloring hair comprising the steps of

a) treating the hair with an oxidative dye in the presence of ammonia and optionally hydrogen peroxide for between about 1 and about 60 minutes;

b) optionally rinsing the hair; and optionally partially drying the hair;

c) treating the hair with a dye composition comprising at least one dye of claim 1 for between about 1 and about 60 minutes; and

d) rinsing the hair.

8. The method of claim 7 further comprising one or more of the following steps:

e) washing the hair with shampoo; and/or conditioning the hair with conditioner after rinsing the hair;

f) rinsing the hair; and

g) optionally drying the hair.