Study On The Mechanism And Application Of Rosin Powder To Improve The Fastness Of Natural Dyes

As the increasing awareness of the dangers of synthetic dyes on the human body andin-depth understanding of global environmental protection, the focus concerned for scholars、consumers and experts is to research and develop the environment-friendly, coo-textiles. So,the natural dyes have been popular again account of their atoxic, easily degradable wastewater, natural luster, harmless, the renewable rich sources, as well as their natural perfumeand pharmacological health functions.However, poor dyeing fastness has been one of themajor factors which prevent the widespread application of natural dyes. For a long time,people tried to improve the fastness of natural dyes mainly through the modification of fibers,the utilization of mordant dyeing, and the application of synthetic fixing agent as well asother methods. While these methods may give rise to some harmful substances to humans andthe environment, thus losing the true sense of natural properties for the fabrics dyed and thegreen nature of dyeing process with natural dyes.Therefore，this papertries to find anotherway to investigated and develop a new natural resin fixing agent. After the liquid wassqueezed from natural plants as raw materials，followed by purification, concentration andcompounding， the natural rosin fixing agent was then produced. By studying itsperformances，fixation mechanism and applications, the optimum fixation process of rosindyeing on cotton fabric was obtained. The cotton fabrics were dyed with the natural dyewhich was extracted by the Phellodendron amurense and fastened by a fixing agent which isprepared from natural rosin powder. The optimal process for fixing was obtained byorthogonal test analysis, in which rosin powder dosage is12%(o.w.f), time is5min, fixingtemperature on60℃, pH is7, and liquor ratio is1:30. Under the optimum conditions, thesoaping fastness and crocking fastness could be improved by1-2levels and0.5-1level.Analysis of XRF，wettability and strength test indicated that rosin powder mainly dependedon cross-linking to form film on the surface of fiber, meanwhile, the role of cross-linkingbetween rosin powder and the hydrogen bonding intermolecular forces were also part of thefixing mechanism of rosin powder. The fixing process has little influence on bursting strength of cotton fabrics, but the wettability of the cotton fiber is decreased.The cotton fabrics was dyed with garcinia mangostana colorant. The optimal process fordyeing and pre-mordant dyeing was obtained by orthogonal test and single factor analysis, inwhich dye concentration is8.5g/L, pH is6, dye temperature is at85℃, dyeing time is for70min, liquor ration is1:40. Meanwhile, the color fastness, evenness and strength of coloredfabric were tested. The results showed that the cotton fabric after dye with garciniamangostana colorant displayed bright shade, good evenness, little loss in bursting strength.Meanwhile the rosin powder was used to treated on cotton and the soft fastness and rubbingfastness were improved by1-2.The properties of color fixing agent of rosin powder was intended to be investigate andcotton fabric was dyed with six different molecular structure of nature plant dyes wereconducted. The fixing effect of cotton has been investigated and discussed after dyeing by thenature dyes. The results showed that fastness and washing fastness were improved，but withdifferent selection of dyes, fixation effect performanced some differences. Then the influenceof molecular structure of dyes on fabric color fixing performance was discussed in this paper.At last, the studies of natural dyes, mainly concentrated in dyeing and in printing littlerelevant research.In this experiment, gardenia, hematoxylin, comfrey, cork, gall, madder sixkinds of natural dyes for printing on cotton fabric,and then, based on the use of CuSO4,FeSO4, KAl (SO4)2as a mordant mordant for processing.Experimental results show that,with non-mordant printing cloth-like phase comparison, CuSO4, FeSO4, KAl (SO4)2mordantafter the six natural dyes printing cloth-like, the same dyes in different types of mordant withthe next color of the not the same, the calico-like shade, brightness and color change occursin varying degrees.Mordant to cloth-like washing and friction, improved fastness, to someextent, but also play the role of a solid color.Rosin powder as one kind of natural colorfixing agent, it has a ecology, environmental protection, green characteristics.In use it withcotton fixative LTG-8080, to enhance the fixative CWF-HR and mordant fixation comparethe performance and found that fixing Effect: Increases fixative CWF-HR> Cotton fixativeLTG-8080> Natural solid toner rosin powder> mordant.It is worth noting that in some naturaldyes printing cloth samples, natural rosin powder fixative effect of fixing the toner fixingcotton LTG-8080is very close to a solid color.Steaming can make the print paste the naturaldye cotton fibers with better binding, increasing the binding force between the two to enhance the printing effect.