Enzyme Wash Process in Garments

Enzyme Wash Process in Garments 

Noor Ahmed Raaz
Specialized in Apparel Manufacturing
Owner and Editor in chief Textile Merchandising
Asst. Prof., Department of Textile Engineering
Atish Dipankar University of Science & Technology
Email: mnnabi@adust.edu.bd

Enzyme Wash:

The enzyme is a living biochemical substances and it works as a catalyst in the washing process. In the washing process at first step enzyme hydrolysis the cellulose and remove the projecting fibers from yarn, therefore faded effects are found by this wash. For getting proper fading effect on garments, enzyme wash is a most essential wash in the garment industry. Now I would like to discuss about this washing step and procedure of enzyme wash.

Process of Enzyme Wash:

There are two types of enzyme are used in the garment washing process. One is neutral enzyme and another is acid enzyme. Neutral enzyme is working in pH 6.5 to 7.5 on the other hand acid, enzyme works in pH 4.5 to 5.5 Enzyme is a living bio-chemical and also sensitive which is not alive below 15 °c and above 55 °c. The total washing process of enzyme wash is done in four steps. Which are discarded as following-

1. Desizing
2. Bio-abrasion
3. Back was
4. Additional Bleaching
   

   Action of enzyme on yarn

Here I try to discuss about washing process of denim garments and weight of garments is 50 kg.

First Step (Desizing):

Desizing is the first step of enzyme wash. This step is use for removing dirt, dust and other foreign martials from garments surface. Here also using wetting agent to hard the garments.

• Water add @ L: R = 1: 5
• Run the machine.
• Desizing agent add @ 0.5 to 2 mg / liter.
• Wetting agent add @ 0.2 to 0.5 mg / liter.
• Temperature: 50°c to 70°c.
• Time: 10 to 15 minute.
• Drop the liquor.
• Cold Wash.

Second Step (Bio-abrasion):

In this step hairy fibers are removed and coloring materials are also removed by the activity of enzyme. If more fading is required then stone has to be used at half the volume of garments.

• Water add @ L: R = 1: 5
• Run the machine.
• Anti back staining add @ 0.2 to 2 mg / liter.
• Acid Enzyme add @ 0.6 to 2%
• pH for acid enzyme” 4.5 to 5.5
• Temperature: 45°c to 55°c.
• Time: 40 to 95 minute.
• Drop the liquor.
• Cold Wash.

Third Steps (Back Wash):

This step is done to resist the activity of enzyme. In this step all the enzyme be dead due to high temperature. Then this dead enzymes and coloring material and other impurities are removed from the garments by dropping the liquor and dye again a rise wash by following process.

• Water add @ L: R = 1: 5
• Run the machine.
• Anti back staining add @ 1 to 3 mg / liter.
• Soda ash add @ 0.3 mg / liter.
• Temperature: 70°c to 80°c.
• Time: 5 to 10 minute.
• Drop the liquor.
• Rinse Wash.

Forth Step (Additional Bleaching):

This step is not mandatory part of enzyme wash. In this process garments be more faded. If any further fading effect is required then this step is done by following process. In this stage use sodium Meta bi-sulphite which help to resist yellow effect on garments.

• Water add @ L: R = 1: 5
• Run the machine.
• sodium Meta bi-sulphite add @ 1 to 2 mg / liter.
• Sodium hypochlorite add @ 0.5 to 5 mg / liter.
• Temperature: 40°c to 50°c.
• Time: 10 to 20 minute.
• Drop the liquor.
• Normal Wash

After Appling the above garment washing process drop the liquor and unload the garments and hydro extracted. At last garments are dried by gas dryer or steam dryer. If any other wash is required from the buyer then this garment is subjected to the other washing process.