The Color Matching System And Combination Dyeing Of Trichromatic Reactive Dyes In Foam Dyeing

As a low add-on technology, foam dyeing can not only save water and energy but also realize zero discharge, replaces quantities of water with air to generate foam and uses foam to apply chemicals and colorants to the textiles. At present, foam dyeing mechanism and process have been researched, but there is rarely report about the combination dyeing of reactive dyes in foam dyeing. In this paper, the research focuses on trichromatic combination foam dyeing of cotton using reactive dyes. The optimal foam dyeing process under the proportions of tertiary mixtures was investigated. The dyeing results were also compared with conventional pad-dyeing process. Color matching triangle with trichromatic dyes was drawn, which provided empirical value as a reference for calculating color-recipe in the computer color matching system.Remozal RGB® dyes(Remozal Red RGB, Remozal Yellow RGB, Remozal Navy RGB) and Anozol M® dyes(Anozol Red M-3BF, Anozol Yellow M-3RF, Anozol Blue M-2GE) were selected as trichromatic reactive dyes in foam dyeing. First of all, the compatibility of selected dyes was studied. Secondly, by single factor experiments, the impact of alkaline agent concentration, stabilizing agent concentration, blow ratio and saturated steaming time on the result of foam dyeing were investigated and color matching triangle with trichromatic dyes was drawn. Finally, the color matching system for trichromatic reactive dyes in foam dyeing was investigated and the establishment of basic database for trichromatic reactive dyes in foam dyeing and their verifying methods in color matching were detailed.The results indicated:The optimal dyeing condition in light color dyeing by foam dyeing with Remozal RGB® dyes was: Na2CO3 15 g/L, stabilizers 0.7 g/L, blow ratio 8, steaming time 1.5 min, respectively. The optimal dyeing condition in deep color dyeing by foam dyeing with Remozal RGB® dyes was: Na2CO3 30 g/L, stabilizers 0.28 g/L, blow ratio 8, steaming time 1.5 min, respectively.The optimal dyeing condition in light color dyeing by foam dyeing with Anozol M® dyes was: alkaline agent 20 g/L, stabilizers 0.7 g/L, blow ratio 8, steaming time 1.5 min, respectively. The optimal dyeing condition in deep color dyeing by foam dyeing with Anozol® dyes was: alkaline agent 30 g/L, stabilizers 0.28 g/L, blow ratio 8, steaming time 2 min, respectively.Remozal RGB® dyes(Remozal Red RGB, Remozal Yellow RGB, Remozal Navy RGB) and Anozol M® dyes(Anozol Red M-3BF, Anozol Yellow M-3RF, Anozol Blue M-2GE) both had good compatibility. Remozal RGB® dyes had high reactivity and low affinity and Anozol M® dyes had high reactivity and high affinity. Remozal RGB® dyes with high reactivity and low affinity are more suitable to low add-on dyeing process than Anozol M® dyes with high reactivity and high affinity. Color strength and fixation rate of dyed fabric with Remozal RGB® dyes were higher than those of dyed fabric with Anozol M® dyes. Compared with conventional pad-dyeing, color strength and fixation rate of dyed fabric were higher than those of conventional pad-dyeing, the dyed fabric had the same washing and rubbing fastness as conventional pad-dyeing and the color shade of dyed fabric was different from that of conventional pad-dyeing. The color triangle, which consisted of 66 dyed fabric samples dyed with trichromatic reactive dyes in different proportions, could provide foundation for computer colorant formulation of the color matching system.The Kubelka-Munk theory with single constant could meet the requirement of foam dyeing color matching. Owing to the interactions among mixed dyes in foam dyeing, the introduction of corrective coefficient to revise Kubelka-Munk theory with single constant could reduce the deviation of theoretical K/S value and measured K/S value.