A Study On The Properties Of Distressing And Rinsing Finishing On Reactive Dyed Denim Fabric

As one of the representatives of fashion, jeans are an everlasting theme, which symbolize youth and energy. For decades, denim products are dyed in indigo. Accompany with the dissatisfaction of consumers with monotonous color, colorized denim products emerge in the market to meet the requirement. Reactive dyes, a prior choice for cotton dyeing, have capacious market space and high value because of their complete color spectrum and superior color fastness to cotton fibers. However, yellowness comes out after rinsing so that they cannot substitute for indigo to lead the market so far.In this article, KMnO4-H3PO4solution is chosen as the oxidation condition. Pick out applicable rinsing processes which are suitable for colorized denim products by testing on reactive dyed denim fabrics. The main procedure and conclusion are summarized as follows:First of all, picking out Procion Red H-E3B、Procion Yellow H-E4R、Procion Blue H-ERD from26kinds of different reactive dyes through a rough washing process. Meanwhile, we find out that the appearance after washing is relevant to the color category directly. There present a series regularity.Secondly, use indigo dyes and reactive dyes to dye denim fabrics respectively by different conditions to determine the optimum process. The optimum process of indigo dyeing is dye concentration1.2g/L, NaOH2.28g/L, Na2S2O43.2g/L and padding-oxidation5times. The optimum process of reactive dyeing is initial dyeing temperature50℃, dyeing for120min, fixation for60min and fixation temperature80℃.Rinsing process are following, the optimum process for indigo dyed denim fabrics is KMnO4concentration15g/L. H3PO4concentration llg/L, rinsing for30s at room temperature. The optimum process for reactive blue dyed denim fabrics determined by Orthogonal Analysis is KMnO4concentration20g/L. H3PO4concentration10g/L, rinsing for75s at70℃of rinsing temperature. The optimum process for reactive red dyed denim fabric is KMnO4concentration 55g/L, H3PO4concentration15g/L, rinsing for75s at85℃of rinsing temperature and the optimum process for reactive yellow dyed denim fabric is KMnO4concentration60g/L, H3PO4concentration15g/L, rinsing for90s at90℃of rinsing temperature.Lastly, there is only one monochloro-s-triazine group in the three reactive dyes which have picked out, so the affinity to cotton fibers is low which can form a similar dyeing process of indigo dyes. Through research, we find out that the " wear white" and "distressed " effect as well as color fastness of these three reactive dyed denim fabrics are more satisfying than indigo dyed denim fabric. The research results can provide theoretical basis and guide tendency for choosing suitable reactive dyes. And it also lays the foundation for a complete reactive dyed denim fabrics rinsing procedure.