• 한국의류학회지
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• 제43권5호
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• pp.753-767
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• 2019

Dyeing behavior of indigo leaf powder was examined in regards to the effect of the amount of pigments on color and dye adsorption for silk dyed by reduction and nonreduction dyeing. The amount of indigotin and indirubin pigments adsorbed in dyed silk was examined by HPLC-DAD analysis. The color of dyed silk showed 7.7BG - 2.7B hue when silk was dyed at $50^{\circ}C$, and 3.5G - 4.9BG when dyed at $70^{\circ}C$. Blue ($b^*$) and green ($a^*$) color decreased as the pH of dyebath increased. When silk was dyed using nonreduction, R (red) and RP (red purple) hue and R hue was more apparent in samples dyed at $90^{\circ}C$. In reduction dyeing, amount of indigotin detected from silk exceeded the amount that was initially contained in the input dye. The amount of indirubin was lower than indirubin that was initially in the powder. In nonreduction dyeing, silk showed a higher amount of indirubin adsorption compared to silk dyed by reduction. The amount of indigotin adsorbed in silk was lower than the amount initially contained in the input dye. The amount of indigotin and indirubin adsorption was primarily dependent upon the dyeing method-reduction or nonreduction along with dyeing temperature and the pH of dyebath.

• 한국의류학회지
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• 제42권2호
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• pp.342-359
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• 2018

This research investigated the relationship between the amount of fixed pigment and the color of silk dyed with three types of fermented indigo powder dye under different temperatures and pH, by reduction or nonreduction method. Amount of fixed pigment was analyzed using the Ultimate 3000 HPLC-DAD instrument and the color of dyed silk was measured using the X-rite spectrocolorimeter. All silk samples dyed by reduction method showed PB color. The amount of indigotin fixation was dependent on the dyeing temperature and pH regardless of the indigotin composition in the dye. Indirubin was less dependent upon the dyeing condition in the reduction dyeing and its fixation was minimum level. Dyeing conditions which can maximize the indigotin fixation were $50^{\circ}C/pH$ 11 and $70^{\circ}C/pH$ 7 conditions in reduction dyeing. Color of silk showed more redness ($a^*$) thus higher PB color when the indigotin fixation was low and indirubin fixation was relatively high. Indirubin fixation was very low with slightly better fixation by nonreduction method. More reddish color was obtained by nonreduction dyeing, and by more alkaline dyebath.