In recent years, new concepts in textile dyeing technology have been investigated which aim to decrease the use of chemicals and the emission of water. In this work, dyeing of cotton textiles with reactive dyes has been investigated in a silicone non-aqueous dyeing system. Compared with conventional aqueous dyeing, almost 100% of reactive dyes can be adsorbed on cotton textiles without using any salts in non-aqueous dyeing systems, and the fixation of dye is also higher (80%~90% for non-aqueous dyeing vs. 40%~50% for traditional dyeing). The pseudo-second-order kinetic model can best describe the adsorption and equilibrium of reactive dyes in the non-aqueous dyeing systems as well as in the traditional water dyeing system. In the non-aqueous dyeing systems, the adsorption equilibrium of reactive dyes can be reached quickly. Particularly in the siloxane non-aqueous dyeing system, the adsorption equilibrium time of reactive dye is only 5–10 min at 25 °C, whereas more time is needed at 60 °C in the water dyeing system. The surface tension of non-aqueous media influences the adsorption rate of dye. The lower the surface tension, the faster the adsorption rate of reactive dye, and the higher the final uptake of dye. As a result, non-aqueous dyeing technology provides an innovative approach to increase dye uptake under a low dyeing temperature, in addition to making large water savings.

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Reverse micro-emulsion dyeing technology shows a high dye uptake and fixation rate, and effectively decreases the amount of waste water in the textile industry. However, the influence of surfactants and co-surfactants on micro-emulsifying water in reverse micro-emulsions has not been investigated. In this study, the micro-emulsifying mechanism in silicone media and the influence of nonionic surfactants and co-surfactants on micro-emulsifying water have been investigated. The results show that a large amount of water can be emulsified using alcohol-polyoxyethylene ethers, especially under 3-5 ethylene oxide groups in molecular structure. As co-surfactant, alcohol which contains 4-9 carbon chains could spontaneously form reverse micro-emulsions in silicone media. The effects of solution pH and ionic strength on the amount of emulsified water were also evaluated. The results show that a large amount of water could be emulsified in silicone media at solution pH 2-9. Meanwhile, the amount of emulsified water decreased with increasing ionic strength. Thus, the optimum conditions for water emulsification are low ionic strength and pH between 2 and 9.

Silk has been widely used not only in the textile field but also in non-textile applications, which is composed of inner fibrous protein, named fibroin, and outer global protein, named sericin. Due to big differences, such as appearance, solubility, amino acid composition and amount of reactive groups, silk fibroin and sericin usually need to be separated before further process. The residual sericin may influence the molecular weight, structure, morphology and properties of silk fibroin, so that degumming of silk is important and necessary, not only in textile field but also in non-textile applications. Traditional textile degumming processes, including soap, alkali or both, could bring such problems as environmental damage, heavy use of water and energy, and damage to silk fibroin. Therefore, this review aims to present a systematic work on environmentally friendly and green degumming processes of raw silk, including art of green degumming process, quantitative and qualitative evaluation, influence of degumming on molecular weight, structure, morphology and properties of silk. It is anticipated that rational selection and design of environmentally friendly and green degumming process is quite important and meaningful, not only for textile application but also for non-textile application.

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Reactive dyes maintain a long reaction with fiber and show a high dye uptake and fixation rate, and effectively decrease the dyeing waste water in siloxane reverse micro-emulsion. However, little research has been carried out into the hydrolysis reaction of reactive dyes in reverse micro-emulsion. In this study, Reactive Blue 19 was selected as a model vinyl sulfone reactive dye to study its hydrolysis in siloxane reverse micro-emulsion. The hydrolysis reaction was analyzed using high performance liquid chromatography. The results show that the hydrolysis rate of vinyl sulfone dyes in siloxane reverse micro-emulsion was slower than that in a traditional bath. Influences due to the ratio of aqueous dye solution to siloxane, non-ionic surfactant, cellulose fiber, and temperature on the hydrolysis reaction of vinyl sulfone reactive dye were also researched. The results show that with more aqueous solution emulsified in the siloxane media, the hydrolysis reaction of vinyl sulfone dye is faster. Reactive dyes were emulsified into a water micro-environment with non-ionic surfactant, which formed reverse micro-emulsion, and decreased the content of free water; this further influenced the hydrolysis of reactive dye.