Supercritical CO₂ Dyeing On Cotton-polyester Knitted Underwear

With the growing awareness of environmental protection,the supercritical CO2 dyeing as its characteristics of no pollution,low energy consumption get more and more attention from all walks of life.The supercritical CO2 dyeing as a new type of green dyeing technology,which possess the characteristics of fast dyeing,no additives,the dyes and CO2 can be reused.Therefore,the industrial application of this technology has its important practical significance for promoting the sustainable development of dyeing industry.So far commodity disperse dyestuffs have always been used in fabrics dyeing in supercritical CO2,and the fabric can only dyed by solid color with no pattern,there are fewer reports on natural dyes dyeing in supercritical CO2 and supercritical CO2 graphics dyeing.Therefore,based on the above problem propose adopting natural dyes to dye polyester-cotton knitted fabrics in supercritical CO2 in this paper.The contrast analysis research on dye effectiveness at different dyeing temperature,dyeing time.dyeing pressure,and dyeing bath ratio was proceeded.At the same time,adopting the stuck method to study polyester-cotton knitted underwear supercritical CO2 graphics dyeing.In this thesis,using three natural dyes(Alizarin,Lawsone,Juglone)to dye polyester-cotton knitted fabric in supercritical CO2 respectively,and it obtains the optimum dyeing conditions of the three kinds of natural dyes.Alizarin:dyeing temperature 115.21?,dyeing time 71.42 min,dyeing pressure 26.22 MPa and dyeing bath ratio 4%.Lawsone:dyeing temperature 104.72.dyeing time 60.00 min,dyeing pressure 25.34 MPa and dyeing bath ratio 4%.Juglone:dyeing temperature 116.44?.dyeing time 67.81 min,dyeing pressure 25.54 MPa and dyeing bath ratio 5%.Therefore adopting natural dyes to dye polyester-cotton knitted fabrics in supercritical CO2,a good dyeing effect can be obtained.Both color fastness to rubbing and color fastness to washing of dyed fabrics are in line with national institute of standards.Furthermore,in this thesis,using two disperse dyes(C.I.disperse blue 79,C.I.disperse red 4)to dye polyester-cotton knitted fabric in supercritical CO2 respectively for studying supercritical CO2 graphics dyeing,and it obtains the optimum dyeing conditions of the two kinds of disperse dyes.C.I.cdisperse blue 79:dyeing temperature 105.85?,dyeing time 62.38 min,dyeing pressure 25.22 MPa and dyeing bath ratio 5%.C.I.disperse red 4:dyeing temperature 104.40?.dyeing time 63.32 min.dyeing pressure 25.01 MPa and dyeing bath ratio 5%.Supercritical CO2 graphics dyeing of the stuck method,which can obtain a good dyeing effect,the dyed graphics possess higher reproducibility.Both color fastness to rubbing and color fastness to washing of dyed fabrics are in line with national institute of standards.