Stonewashing added a new dimension to denim garments in the late 1970s: the process enabled artificial ageing of denim garments which imparted a fashionably aged look. As the name 'stonewashing' implies, the blue jeans were washed with pumice stones to achieve a faded look.
Due to the disadvantages of using pumice stones, such as-
Machine damage
blocking of the drainage system
difficulty in removing pumice-stone residues
excessive damage to garment hems and seams
large amount of stone required for small batch
So the alternative methods for stonewashing were developed. Cellulose enzymes were introduced in the 1980s as a denim-washing, aid to achieve a faded and abraded look similar to that provided by pumice stones. Cellulose works by loosening the indigo dye on the denim in a process know as 'biostonewashing'. A small dose of enzyme can replace several kilograms of pumice stones.
Biostonewashing has opened up new possibilities in denim finishing by increasing the variety of finishes available. For example, it is now possible to fade denim to a greater degree without running the risk of damaging the garment. Productivity can also be increased because laundry machines contain fewer stones or no stones and more garments. The use of less pumice stone results in less damage to garment and machine, and less pumice dust in the laundry environment.
A range of celluloses for denim finishing, each with its own unique properties, is available in the market. These can be used either alone or in combination with pumice stones in order to obtain a specific look. An ideal biostone wash enzyme would possess high abrasive activity (the ability to remove indigo from denim) as well as low back staining with lower fabric strength loss.
Celluloses have been used for the past twenty years and it is estimated that approximately 80% of denim garments are processed in this way. Celluloses are enzymes that are specific for the hydrolysis of the beta-1, 4 glucose linkage of cellulose. The reaction mechanism of the naturally occurring cellulose enzymes on cellulose is very complicated and several different enzymes endoglucanases, cellobiohydrolases and beta-glucosidases are synergistically involved in the chain of reactions needed to break down cellulose into glucose. The first type of celluloses introduced to market was derived from the Trichoderma family, a fungus with the longest history of cellulose research. The second phase in the, development of cellulose was the introduction of products based on another fungus called Humicola insolens. These celluloses soon became known as the neutral celluloses, as they could work in a more neutral pH environment. A special feature of the neutral celluloses is their ability to provide the stonewashed look with minimal indigo redeposition during the treatment. Thus the jeans and other denim garments would have a higher contrast between white and blue yarns, and the inside pockets as well as the leather labels would not be stained with indigo. However, the reaction time of this enzyme is slow and its use requires a longer processing time.
Since then, much progress has been made in the development of cellulose compositions, which are customized to achieve specific applications. Research and development activities have been focused on a new generation of cellulose enzymes whose composition has been altered through genetic engineering to provide higher abrasion contrast, reduced back staining, improved fabric-strength retention and broadened operating pH and temperature ranges. The development of modern biotechnology brought new tools for scientists to create new, better cellulose products for textile applications.
Benefits:
Valumax A 376 is a high-per formation. Ready-to-use cellulose for the abrasion of denim (stone washing) .this produce allows new shades and finishing to be created and cost-effectively in an environmentally friendly way.
High color contrast finish
Low degree of indigo back staining
Optimum strength retention
High degree of reproducibility and reliability
Maximized fabric strength retention
Improved wash look or creation of new looks
Easy handling
Cost effectiveness
