Effects Of Enzyme Washing On The Shade Of Reactive Dyes

Cellulase is widely applied to bio-polishing,stone washing and softening finishing of cotton fabric.It’s effective to remove the cellulose fibril,improve fabric surface gloss and enhance the wearability of cotton fabric.For energy-saving emission reduction,industrial production introduces a new type of enzyme washing that its combination application with dyeing in one-bath process.The shade of reactive dyes is easy to change in the process.To reduce the impact of enzyme washing on the shade of reactive dyes,the paper makes sure the change degree of the shade by enzyme washing through the study of enzyme washing process,analyzing the causes of shade changing and improving the original enzyme washing process.First of all,the polishing effect of two kinds of cellulase on cotton fabric was studied.The optimum polishing conditions were determined by single factor experiments.Experiments show that the optimum process of acidic cellulase concentration is 3%(owf),the temperature of enzyme washing is 55℃,p H=4.5,enzyme washing time is 45 min,the bath ratio is 1:10;neutral cellulase concentration is 3%(owf),enzyme washing temperature is 50℃,p H=6.5,enzyme washing time 45 min,the bath ratio is 1:10.The polishing effect of acidic cellulase was better than that of neutral cellulase,but the effect on shade is much higher than that of neutral cellulase.Therefore,the optimal cellulase is neutral cellulase.Secondly,the two techniques of enzymatic washing were explored.The single factor experiment was used to study the influence of factors that affecting the shade of reactive dyes.Under the different dyeing concentrations of 2% and 5%,the effects of enzyme washing on the shade of different color reactive dyes were researched.At the same time,the effect of a new one-bathing dyeing process on the shade of reactive dyes was discussed comparing with primary process by the single factor and orthogonal experiment.And the main reason and mechanism of the three processes were analyzed systematically.The results showed that the new enzyme washing process has more influence on the shade of the reactive dyes than the two traditional processes,and the biggest influencing factor is cellulase concentration.It is difficult to solve the optimization problem caused by the one-bath process only by orthogonal experiment.Through the discussion of the change on the shade of different color dyes,it is found that the color of the fabric is lighter,the brightness is increased,the color is slightly decreased,and the hue angle is approximately similar.Under the action of cellulase concentration of 5%,the ΔL of other dyes are greater than 0 and less than 2,and the absolute value of ΔC is less than 1.5,and ΔH was less than 1 except for active brilliant blue RSP and active turquoise blue HF.According to a large number of experimental demonstration and process comparison,the main influence of the shade on the following functions and mechanisms:(1)The impact of fabric surface finish on the shade of reactive dyes.(2)The reaction of reactive dyes and enzymes impacts on the shade of reactive dyes.(3)Effect of cellulase hydrolyzate and dye on the shade of reactive dyes.Mainly glucose on the dye space and electrostatic repulsion and the role of glucose itself,the nature of polyol and the role of the dye.Then,according to the analysis of the reason which the shade changes,the solution is put forward,and the feasibility of the project and the optimization of the experimental process are discussed by single factor and orthogonal experiments.The experimental results show that the present study can effectively reduce the influence of cellulase in the follow-up dyeing process by adding inhibitor,but cannot eliminate the affection by hydrolysate,subsequent researchers need to find better inhibitors.To improve the production process can effectively reduce the influence of shade,and compared with the original process,the chromatic aberration value decreased from 2.76 to 1.47.The optimum conditions are as follows: the amount of reactive dyes is 3%,the dosage of is 60 g/L,the amount of enzyme is 3%,the time of enzyme washing is 40 min,the temperature is 50 ℃,the p H is 6.5,the bath ratio is 1:10.Finally,to verify the feasibility of improved technology,it is applied to the sample test.The results show that the improved process has little effect on the shade of reactive dyes compared with the original process,the chromatic aberration value decreased from 2.16 to 1.28,the anti-pilling performance decreased 0.5 grade,the surface finish and the polishing effect is good,and the production can meet the needs of the customers.