Modified indigo compounds and methods of dyeing a substrate using a modified indigo compound
The present disclosure provides dye compounds for use in dyeing textiles.
1. A dye compound for use in dyeing a substrate, the dye compound comprising an indigo derivative, or a salt thereof, having one or more modification over the chemical structure of indigo, wherein the indigo derivative has a water solubility of greater than 0.2% w/v in the absence of a reducing agent and in the presence of oxygen, and converts to indigo upon removing the modification, and wherein the indigo derivative is of Formula (Ia) or (Ib)
wherein X is selected from the group consisting of acetate, propionate, lactate, citrate, tartrate, succinate, fumarate, maleate, malonate, mandelate, phthalate, phosphate, nitrate, sulfate, ethanesulfonate, phosphonate, napthalenesulfonate, benzenesulfonate, toluenesulfonate, camphorsulfonate, methanesulfate, ethanesulfonate, napthalenesulfate, benzenesulfate, toluenesulfate, camphorsulfate, bisulfate, sulfite or bisulfite.
2. The compound of claim 1 , wherein the compound is
3. A kit comprising: (i) one or more compounds of claim 1 ; and (ii) a reagent and/or device that converts the compound to indigo.
4. The kit of claim 3 , wherein reagent (ii) comprises a base, a device that generates heat, or a device that generates steam.
5. A method of dyeing a substrate, comprising: (i) contacting the substrate with an aqueous bath comprising a compound of claim 1 ; and (ii) hydrolyzing the compound of step (i).
6. The method of claim 5 , further comprising repeating steps (i) and (ii).
7. The method of claim 5 , wherein the aqueous bath further comprises a stabilizing agent that is NaCl, Na 2 SO 4 , or combinations thereof.
8. The method of claim 5 , wherein the hydrolyzing is performed using a base, heat, steam, or a combination thereof.
9. The method of claim 8 , wherein the base is a hydroxide base, an alkaline earth base, or a carbonate.
10. The method of claim 8 , wherein the base is a hydroxide base that is sodium hydroxide, potassium hydroxide, or lithium hydroxide.
11. The method of claim 8 , wherein the base is a carbonate selected from sodium carbonate or potassium carbonate.
12. The method of claim 8 , wherein heat comprises a temperature of at least about 80° C.
13. The method of claim 5 , further comprising: (iii) rinsing the substrate from step (ii).
14. The method of claim 13 , wherein the rinsing is performed with an aqueous solution comprising a neutralization agent or buffering agent.
15. The method of claim 13 , further comprising: (iv) pretreating the substrate prior to step (i) with a cationic agent or caustic agent.
16. The method of claim 15 , wherein the cationic agent is selected from diallyldimethylammonium chloride, polymerized diallyldimethylammonium chloride, [2-(acryloyloxy)ethyl] trimethylammonium chloride, 3-chloro-2-hydroxylpropyl trimethyl-ammonium chloride, or a combination thereof.
17. The method of claim 15 , wherein the caustic agent is selected from sodium hydroxide, potassium hydroxide, sodium carbonate, diethanolamine, trimethylamine, hexamethylenediamine, liquid ammonia, or a combination thereof.