Study On Decolorization Of A Recycled Wool Fabric And Dark Dyeing

With the rapid development of China's economy and continuous rise of fast fashion trends,consumers have higher and higher requirements for textiles,and the consumption of textiles is also increasing day by day.The production and use of textiles have led to a large amount of waste textile materials.At present,the main disposal methods of waste textiles are landfill and incineration.As a kind of protein fiber,wool fiber will cause certain damage to the environment whether it is disposed of by landfill or incineration.Meanwhile,China is witnessing a decrease in wool production and imported wool content year by year and is also facing the shortage of textile raw materials.Therefore,recycling waste wool is very necessary.whether from the perspective of reducing environmental pollution,saving resources or improving efficiency.The burrs and waste wool products produced in the production process are opened and mixed,carded and woven into fabrics called recycled wool fabric.Due to the variety of fiber sources,different colors and complex compositions,it is challenging to achieve the deep and bright color dyeing of recycled wool fabric.Based on the above situation,this paper mainly involves two aspects of work: First,the paper analyzed the composition of a pair of recycled wool fabric and completed the decolorization of recycled wool fabric in order to lay the foundation for the development of the colorful dyeing process of recycled wool fabric;Second,it explored the dyeing properties of recycled wool fabric,analyzed the reason of low wet rubbing fastness of wool fabric and determined the deep black dyeing process of recycled wool fabric.The specific research results are as follows:1.The paper analyzed the composition of the recycled wool fabric,used different chemical solvents to dissolve different types of fibers and calculated the proportion of the fiber in the recycled wool fabric.The results shows that in the recycled wool fabric the content of the wool fabric accounts for 98.46%,polyester fiber accounts for 1.21%,spandex fiber accounts for 0.14%and viscose fiber accounts for 0.19%.2.The decolorization process of recycled wool fabrics was explored.By observing the microstructure of wool fibers after treatment as well as making the K/S value of recycled wool fabric,the standard deviation value Sr of the color of recycled wool fabric and the breaking strength of decolorized fabrics used as evaluation indicators,the decolorization process of the recycled wool fabric was determined as follows: the dosage of hydrosulfite is 70 g/L,the dosage of sodium carbonate is 12 g/L,the dosage of SDBS is 4 g/L,and the treatment is 70 ? for 10 min.3.In the paper the dyeing properties of recycled wool fabric and full wool fabrics were compared;the dyeing properties of Delosol black CE,Weinersu deep black PV-EW,weak acid black BR and Lanaset Black B GR on the two fabrics were researched;the dye uptake rate,K/S value and rubbing fastness were tested;and the reasons for the difference in dyeing properties between recycled wool fabric and full-wool fabrics were analyzed.Thus,the recommended dark-color process for the dyeing of recycled wool fabric is as follows: Delosol black CE should be used,the dye concentration is 6% owf,the dyeing temperature is 90 °C,the dyeing holding time is 40 min,the amount of acetic acid is 6% owf,the amount of leveling agent Albegal B is1 g/L,the amount of sodium carbonate is 8 g/L,fixing temperature is 85 ? and fixing time is20 min.By observing the K/S value of the dyed fabric,the standard deviation value Sr of the color,and measuring the rubbing fastness and various soaping fastness of the soaped fabric,the type of soaping agent is determined,which is the standard synthetic detergent with 80 °C soaping temperature,15 min soaping time,and 2 g/L standard synthetic detergent.