Dyes with changeable solubilities, and methods for their use
View Patent ↗Solubility changeable dye compositions include a dye component linked via a linker moiety to a stimulus responsive hydrophobic moiety which modulates the solubility of the dye, wherein the hydrophobic moiety is configured to be de-linked from the dye component on exposure to a stimulus and render the dye component more hydrophilic. A method of dying a substrate with such dye compositions includes contacting the dye with the substrate.
1. A method of dying a substrate, the method comprising:
contacting the substrate with an aqueous solution of a dye compound for a time period sufficient to covalently bond a hydrophilic dye moiety of the dye compound to the substrate; and
exposing the substrate to a stimulus;
wherein:
the dye compound comprises:
the hydrophilic dye moiety; and
a hydrophobic moiety bonded to the hydrophilic dye moiety through a linker moiety; and
the linker moiety is configured to be cleaved in response to a stimulus;
the dye compound is represented by Formula I, II, III, or IV:
Z is the hydrophobic moiety;
L is the linker moiety;
Y is a phenyl or a naphthyl group;
X is H, Cl, Br, F, or I;
R a is a halogen, or —NR b —W group;
R b is H or an alkyl group;
R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , and R 7 may be the same or different and are independently H, Cl, Br, F, I, —NO 2 , —OH, alkyl, aryl, or —S(═O) 3 R 12 ;
R 8 , R 9 , R 10 , and R 11 may be the same or different and are independently H or alkyl;
R 12 is H or an alkali metal;
each Y independently comprises a phenyl or a naphthyl group; and
W comprises a phenyl, naphthyl or anthracenyl group.
2. The method of claim 1 , wherein the substrate comprises fabric, paper, plastics, glass, metals, wood, hair, fur, oils, waxes, leather or food.
3. The method of claim 1 , wherein the substrate comprises a fabric or a textile.
4. The method of claim 1 , wherein the stimulus is heat, photolytic, or enzymatic.
5. The method of claim 1 further comprising washing the substrate to remove a non-covalently bound dye compound, after exposing the substrate to a stimulus.
6. The method of claim 1 , wherein the contacting comprises soaking the substrate in an aqueous solution of the dye compound.
7. The method of claim 1 further comprising raising the pH of the solution to about 12 after the contacting.
8. The method of claim 1 , wherein the exposing the substrate to the stimulus comprises heating the substrate.
9. The method of claim 8 , wherein the heating of the substrate comprises heating the substrate to about 140° C.
10. The method of claim 1 , wherein the exposing the substrate to the stimulus comprises photolyzing the substrate.
11. The method of claim 10 , wherein the photolyzing is conducted with a wavelength of light at about 400 nm.
12. The method of claim 1 , wherein the exposing the substrate to the stimulus comprises exposing the substrate to an enzyme.
13. The method of claim 12 , wherein Z comprises a fatty acid chain.
14. The method of claim 1 , wherein Z is an alkyl group, a cycloalkyl group, or an aryl group.
15. The method of claim 1 , wherein L is a direct bond, an ester, ether, amide, carbonyl, phosphate, sulfoxide, nitrophenyl, nitrobenzyl, alkoxybenzoin, phenacyl, or benzylthioether group.
16. The method of claim 1 , wherein the Z and L comprise a 2-nitrobenzyl group.
17. The method of claim 1 further comprising removing the substrate from the aqueous solution.
18. The method of dying a substrate, the method comprising:
applying an aqueous solution comprising a reactive dye to the substrate;
waiting for exhaustion;
raising the pH of the aqueous solution to fix the dye to the substrate; and
exposing the substrate to an enzyme to cleave the dye molecule into a fatty acid and a hydrophilic dye.
19. The method of claim 18 further comprising rinsing the substrate with water.
20. The method of claim 18 , wherein the enzyme is a lipase, a nucleoside, a nuclease, or a protease.