1. GREEN UNIVERSITY OF BANGLADESH
Department Of Textile
Lab Report
Course Code : TE 413
Course Title : Apparel Manufacturing III Lab
No Of Experiment : 05
Name Of Experiment : Study on Enzyme washing process of denim
garment
Remarks:
Submitted By:
Name : Md Rakibul Hassan
ID : 183014057
Section : E2
Department : Textile
Submitted to:
Name : Jannat Jahan Joya
Designation : Lecturer
Department : Textile

2. Experiment No: 05
Experiment Name: Study on Enzyme washing process of denim garment
Introduction :
Enzyme wash is an environmentally friendly wash due to the natural origins of enzymes. It is also a
popular garment washing process. To reduce the adverse effect of stone wash, the garments are
washed by using enzymes. The enzyme breaks the surface cellulose fibers of the fabric and removes
them during washing. The enzymes can be stopped by changing the alkalinity of the bath or its
temperature when the desired color will be achieved. During enzyme washing, a certain amount of
indigo dye and cellulose fibers from the surface of the fabric are removed. The rest of the processes
of enzyme washing includes final rinsing and softening. There are two types of enzymes 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
Objectives:
1. To learn about engyme
2. To learn about engyme wash
3. To learn about engyme washing process of denim garments
Description:
Types of engyme wash:
• Acid Enzyme
• Neutral Enzyme
1 . Acid Enzyme :
Acid Enzyme works in acidic medium. First need to fix the ph level to 4.5 by acetic acid to make it a
acetic solution then using the enzymes into solution. They are very highly abrasive and used in liquid
form. During this wash heavy backstaining occurs and it works faster. Stone used to get more abrasion
and faster result to attain the desired outlook.Acid enzymes are added according to the design of the
final garment. The process sequence of acid enzyme wash is given below :

3. Process Sequence of Acid Enzyme Wash
Water is added ( Let, M:L = 1:60 )
↓
Machine started running
↓
Acid Enzyme added ( let, 2 g/L )
↓
Acetic Acid Added ( Let , 1 g/L )
↓
Antibackstainer ( Let , 1 g/L )
↓
Pumice Stone added ( Let , 10 Kg)
↓
Steam to raise temp 45°C ( PH = 4.5 )
↓
Process time 20 minutes
↓
Drop the liquor
2 . Neutral Enzyme :
Neutral enzyme works in neutral solution. Their abrasive capacity is very low and normally stones
are used in this washing. Neutral enzymes are found in powder form. Backstaining is less and gives
slower result in neutral enzyme wash. The process sequence of neutral enzyme wash is given below
:
Process Sequence of Neutral Enzyme Wash
Water is added ( Let, M:L = 1:60 )
↓
Machine started running
↓
Neutral Enzyme added ( let, 2 g/L )
↓
Antibackstainer ( Let , 1 g/L )
↓
Pumice Stone added ( Let , 10 Kg)
↓
Steam to raise temp 45°C
↓
Process time 20 minutes
↓
Drop the liquor
Working Procedure:
1. At first, the required amount of garments are loaded into the machine.
2. Garments are de-sized here by using de-sized chemicals.
3. After completing the de-size process, garments must be rinsed two times to remove the size material
from the garments.
4. Here, the required amount of enzyme (Acid or neutral enzyme) should be added by following M:
L ratio.
5. If the acid enzyme is added to the machine, then PH should be adjusted here in the required range
(4.5-5.5) by adding acetic acid (CH3COOH).
6. Here, the required temperature should be maintained for the different enzymes
7. Garments are tumbled here for 30-60 minutes which depends on the shade.
8. Here, the garments are rinsed two times to remove starch from the garments.
9. Garments have produced a soft effect here by using softening chemicals (Anti ozone softener)

4. 10. After completing all the above processes, the garments are extracted here and send to the drying
section.
11. Finally, all the clothing are dried here by using a gas dryer or steam dryer(depending on the shade)
Conclusion:
After completing the experiment we have learnt about enzyme wash and enzyme washing of denim
washing. This experiment will be really helpful to our future life. We are grateful to our course teacher
for assigning this experiment.