CELLULASE ENZYME
Stones are not only abrasive to garments but also to the equipment.
Stones can create sludge in waste treatment systems.
Cellulase enzyme is a particular strain of enzyme derived from microorganisms selective to cotton form of cellulose and not to starch. They attack 1 - 4 beta glucoside linkages resulting in reduced molecular weight and therefore removal of surface fiber.
Main factors that control enzyme washing:
1 - pH
2- temperature
3- time
4 - concentration
5 - mechanical action
Once the reaction takes place, the mechanical action between garments and
equipment as well as between garments femoves weaker fibers resulting a cleaner,
smoother surface. Stones may be added to enhance the abrasion.
TYPICAL PROCEDURE FOR CELLULASE ENZYME WASHDOWN (TWO STEP PROCEDURE)
Load garments (addition of stones optional)
Desize for starch
- alpha-amalase enzyme or
- oxidative desize
Rinse
Adjust pH to 4.5 - 5.0 with
- acetic acid or a buffer system
Heat to 50 to 60 C ( 122 - 140 F)
Add cellulase enzyme
Tumble for 30 - 60 minutes
*Deactivation step - rinse hot > 65° C
Rinse cold
Soften and/or optically brighten
Tumble dry
*Deactivation of the cellulase enzyme to prevent further weight reduction
can be done by temperatures in excess of 60 C (140 F) and/or at a pH
higher than 5.0.
Cellulase enzymes may be used as an aftertreatment to clean up surfaces of garments which have become fuzzy during garment dyeing. The shade of the dyed garments may change which requires preliminary lab work to determine if this will be a problem or not.
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