Application of Fluorescence Spectroscopy in Indigo Reduction Process : Identification of Reduction Stages and Reduced Indigo Concentration

Fabrication of ballpoint-ink via encapsulating inorganic pigments in microemulsion gels

“…The red pigment [Fe(SCN) 3 ] À2 was prepared from the reaction of Fe(NO 3 ) 3 and KSCN precursors according to eqn (3).…”

“…1 Various inorganic salts have been used as auxiliaries in the textile and dyeing industries for several centuries. [2][3][4] Nowadays, indigo obtained from inorganic salts has not lost its importance because it offers better stability, especially oxidation resistance, compared with organic pigments. 5 However, research on the solubility of inorganic compounds might play an essential role to unlock the physical and chemical aspects of thermodynamics and kinetics of the molecules microscopically, hence this understanding may be helpful for future advanced research, such as in nanotechnology, [6][7][8] nanophotonics, 9 nanocoatings, 10 solar cell fabrication, 11 membrane therapy, 12 drug delivery to cancer cells, anti-counterfeiting material coatings, 13 optical sensors, 14 etc.…”

Indigo reduction by using microorganism: Comparison of reducing power between Dietzia sp. KDB1 and yeast (Saccharomyces cerevisiae)

“…Since yeast is active in weak acidic conditions, there appears to be a rapid pH drop at the earlier stage of the yeast reduction. 12 Even when the pH is adjusted for the initial pH drop, the decrease in pH of the yeast system is greater than that of the KDB1 system at the same elapsed time. This is mainly due to the metabolic process that generates organic acid and decreases the buffer capacity of the yeast.…”

“…10 To evaluate the reducing power of KDB1, oxidation-reduction potential (ORP), colour strength (K/S), and fluorescence intensity (FI) were used at given conditions of microorganism concentration, temperature, and pH. 11,12 Summarising the researches performed until now, KDB1 reduction is less efficient in reducing power than inorganic reduction, even under optimal condition of pH and temperature. Moreover, the reducing power of the KDB1 reduction reaches a maximum level after a couple of days and then decreased gradually with elapsed time.…”

Cleaning iron rust compounds from cotton textiles: application to Qing Dynasty armor

“…This is because the indigo dye is insoluble in water, making it difficult to fade on the fiber. Even though the indigo is reduced to leuco vat acid (II) in an acidic aqueous solution, its solubility is extremely low, and it is equally difficult to fade [30,31]. As a result, the cleaning process has no impact on the indigo color and can be used to remove rust compounds from the fabric dyed with indigo.…”