How to increase indigo solubility

The dyeing process of indigo dye is through the reduction and oxidation of two chemical reactions, dyeing adsorbed on the fiber cryptochrome by the oxidation of air or other oxidizing agents, the reversion of insoluble reducing dyes and fixation on the fibers, so as to make the fibers dyed with color. Indigo is insoluble in water, alcohol, ether and benzene, almost insoluble in dilute acid or dilute alkali solution, but soluble in concentrated sulfuric acid, also soluble in boiling phenol, nitrobenzene or aniline. 290 ℃ sublimation. 390 ~ 392 ℃ decomposition.

Indigo dyes are water insoluble polycyclic aromatic compounds, the basic feature of their molecular structure is that in the molecular **** conjugated double bond system contains two carbonyl groups, and carbonyl carbon atoms must be the carbon atoms in the aromatic ring, the carbonyl group in alkaline solution with the role of the insurance powder phase and is reduced, transformed into hydroxyl, hydroxyl compounds cryptochromic acid, and become water soluble in the sodium salt of the reductant body, i.e., cryptochromic body.