Patent ID: 8366791

Claim:
A formulation for dying hair, comprising: a. a catechol-based dye precursor; b. an oxidizing agent; and c. water; wherein the formulation for dying hair is substantially free of organic solvents, co-solvents and diluents, and wherein the catechol-based dye precursor is of the formula wherein R 1 and R 2 can be the same or different and are: H, alkyl of 1-4C, NH 2 , OH, COOR′, CONH 2 , halogen, OR″, CH 2 OH, CH 2 NH 2 , CONR′R″ wherein R′ and R″ can be the same or different, wherein R′ is alkyl of 1-4C or H, wherein R″ is alkyl of 1-4C; R 3 is H or alkyl of 1-4C or COR″; R 4 , R 5 can be the same or different and are: H, alkyl of 1-4C, NH 2 , OH, COOH, CONH 2 , halogen, OR″, NO 2 , SO 3 R′, HNR″, or NR″R″ or any pharmaceutically acceptable salts thereof or mixtures thereof, and wherein when R3 is H or alkyl, R1 is alkyl of 1-4C, NH 2 , COOR′, CONH 2 , halogen, OR″, CH 2 OH CH 2 NH 2 , CONR′R″ wherein R′ and R″ can be the same or different, wherein R′ is alkyl of 1-4C or H, wherein R″ is alkyl of 1-4C.