Study Of Printing On Silk With Natural Dyes

As people's living standard rising, the requirement of textile for ecology, healthy and safety was more and more high, thus, the application of natural dyes in textile dyeing was widely researched, but there was fewer study for printing. This paper studied the optimum paste and mordant for natural dyes printing, from the selection of the paste and the influence of mordants to dyes and paste.The optimum printing for natural dyes, different mordants printing fabric's colors and the fastness of printed fabrics were studied.In this article we chose some different structural natural dyes, studied the paste, metal ions and natural dyes'compatibility. The research result showed that except synthetic gum tragacanth, the rest several pastes'compatibility with natural dyes were very good, fluid curve virtually unchanged. The influence of Fe2 + to pastes was relatively great, in which sodium alginate was unstable to metal ions, easily to become gel. The influence of Fe3 + to natural dyes'color tone and stability was great, and it was easy to complex with dyes.It was found from the gardenia yellow and mulberry red printing effect that, gardenia yellow printing fabric's color irregularity was 0.25 when guar gum as the paste, contour definition was 99.7%, dyes transfer rate was 93.6% and paste taking-off rate reached 87.3%. Meanwhile, Mulberry red printing fabrics'olor irregularity was 0.15 when sodium alginate as the paste, contour definition was 97.8%, dyes transfer rate was 96.4% and paste taking-off rate reached 98.4%. Both of the pastes used can meet the need of silk printing.Afterward the optimum printing conditions of gardenia yellow and red mulberry has been obtained through the single-factor experiment. The results indicated that the optimum printing process of gardenia yellow was that, 100℃of steam temperature, steam for 10min in saturation steam condition. When the dye concentration versus original paste reached 3% , the printing color depth almost achieved the maximum value. The optimum printing process of red mulberry was that, 100℃of steam temperature, steam for 20min in saturation steam condition. When the dye concentration versus original paste reached 4% , the printing color depth almost achieved the maximum value. From the mordent printing of different natural dyes, it was found that the products'washing fastness and light fastness of copper printing were superior to other mordants. Among which, gardenia blue,sodium copper chlorophyllin, safflower yellow and carmine printing fabrics'washing fastness with copper mordant can reached level 4; safflower yellow, carmine and lac red dyes printing fabrics'light fastness can reached level 6 while Cu2+, Fe2+ and Fe3+ as the mordants.