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A novel anti back staining method for denim garments

Denim and its various items like pants, shirts, jackets,belts, caps, etc, are the most preferred clothing for todays youth. This studydiscusses compositions and methods of reducing or preventing back staining ofindigo dyes on the weft yarn and pocket of denim garments. The dye, as it is removedfrom the denim material, post treatment with cellulase or by a conventionalwashing process may cause back staining or re-deposition on the denimmaterial; e.g.: re-colouration of blue threads and blue colouration of whitethreads, resulting in less contrast between the blue and white threads.Get more news about pocket anti back staining agent,you can vist our website!
Introduction:

Denim garments are looked at as a major trend setter by our youth.The spread of denim culture all over the world brought with it a trend of fastchanging fashions. One after another several washes were introduced such asstone wash, acid wash, moon wash, etc. Over the last decade, India has probably seen the most dramatic and exciting changes in the washing of denimgarments. As per the denim garment export market, this high quality garment hassuperior aesthetics and great value for price. In terms of the quality aspect,back staining plays a vital role in improving the appearance of the denimgarment.

Back staining: Back staining implies soiling of the weftthread and the pocket lining by detached indigo or its reduced leuco form. Backstaining mainly occurs during desizing or stone washing or enzyme stonewashing.
Chemistry of Back Staining:
During stone washing or enzyme washing, cellulose isdegraded and indigo dye is released. For instance, the cellulase enzymes aretemporarily bound to the cellulose by means of an anchor. This gets split in termsof 1,4-β glycoside composition. After this process it is made availablefor further hydrolysis reaction.
Endo Gluconases: By means of the endo gluconases the cellulose is dissociated in a statistically distributed sequence.
Exo Gluconases: The exo gluconases dissociate the cellulose chains into glucose molecules from the unreduced end.
Cellobiohydrolasis: Separation of cellobiose (double bond glucose molecule) from the unreduced end of the cellulose.
β- Glucosidasis: Dissociation of the cellobiose into glucose molecules.
As seen from the picture, the cellulase is degraded hydrolytically by cellulases partially until it becomes glucose. The glucose is partially able to reduce the indigo, both on the fibre and in the treatment liquor. This reduced form has low affinity to cellulose fibre and thus soils the weft thread and the pocket lining. This is also assisted by alkaline conditions and the temperature of the wash bath.

The acid cellulase enzymes have a strong effect on cellulase hydrolysis and create more glucose formation, resulting in increased back staining of the denim garment. Neutral cellulase has its optimum pH at 6-8 at temperatures of 50 60C. Compared to acid cellulase they have a less negative effect on the tensile strength; hence there is less back staining.
As a whole, obtaining a good contrast between the blue and white yarns is often described as minimised back staining. The contrast is the difference between the blueness of the blue yarns and the whiteness of the white yarns. But this is difficult to quantify. Therefore, back staining can be quantified by measuring the re-deposition of indigo on white denim.