The aim of this project is to find out the changes that occur in physical properties of denim when it is subjected to enzyme stone and acid wash or to find out the impact of enzyme stone and acid wash. 97% cotton 3% elastomer twill, weave 3/1, construction 72 × 40/9 × 7 indigo dyed denim fabric leg panels as per lab standard recipe are used here to examine. Firstly, desizing was done as pre-treatments and after treatment was silicon softener. After washing process, different samples from both washing are going to express different behavior on physical properties. This experiment is done to find out the discrimination in tearing strength, shrinkage %, color fastness to wash, color fastness to rubbing, pH rate between stone enzyme wash and acid wash of denim garments.
Denim clothes have a lot of demand in the market of regular clothes as well as in the fashion market. People of all ages, especially the youth have a great interest in the denim [
Among different techniques of cloths washing, enzyme is chosen to fade color from all over the cloths in a regular manner and to polish the surface of the fabric [
Using pumice stone causes wear and tear of the cloths and the machine surface. Enzymatic treatments have a lot of advantages over stone washing but the stone has a different irregular effect on the cloths which is very difficult to achieve with only enzyme [
During Acid wash, pumic stones are used. By the action of pumic stones, an irregular fading effect is developed on heavy clothes like denim, thick canvas/twill, and sweater [
This paper investigates the impact of enzyme-pumice stone wash on the physical and mechanical properties of denim cloths as these properties determine the wearers’ feel and life of the end product [
To perform a successful experiment the following materials, instructions and methods are used in this project.
97% cotton and 3% elastane denim fabric were used. These comprised bluish denim fabric, GSM 358, 3/1 warp faced S-twill, construction 72 × 40/9 × 7, fabric width 57 inch. Then sewn 2 leg panel.
Washing Laboratory Departmental Pacific Jeans Ltd., CEPZ, Chittagong.
Types of machines used for washing which are shown below in
Specification:
Name of the machine: Washing machine;
Brand: Mathis;
Origin: Switzerland;
Model: GW-5;
Serial No: 140472;
Rated Power: 3W-380V;
Weight: 55 Kg.
Specification:
Name of the machine: Dryer machine;
Brand: SIEMENS;
Origin: China;
Model: WD12D523.
A Leg panel was taken for this experiment which is 200 gram. At first, the leg panel was taken for desizing treatment then Stone enzyme wash is done. After washing and drying, various test is done. The process parameters are given below.
Desizing
Fabric weight: 0.2 kg;
Water: 1.8 liters;
Temperature: 50˚C;
Desizing agent: 1.08 gm;
Anti-Back staining agent: 1.8 gm;
Time: 15 min.
Stone enzyme wash
Water: 1.6 liters;
Pumice stone: 0.1 kg;
Temperature: 45˚C;
Neutral Enzyme: 2.7 gm;
Anti-Back staining agent: 1.44 gm;
Acetic Acid: 1.08 gm;
Time: 15 minutes.
Bleach wash
Water: 1.6 liters;
Bleaching agent: KMnO4 (18 gm);
Temperature: 60˚C;
Time: 10min;
Neutralization;
Sodium Hyposulphite (5.4 gm) is used for neutralizing.
Hydro extraction
Hydro-extraction is done for 1.5 min to extract all the excess water from the fabric.
Dryer
Steam drier is used to dry the fabric. Machine is run for 20 minutes.
1) Desizing
Garments are loaded
↓
Water is added (1.8 liter)
↓
Machine started running
↓
1.08 gm Soda Ash added
↓
1.8 gm Anti back staining agent added
↓
Steam to raise temp 50˚C
↓
Process time 15 minutes
↓
Drop liquor
↓
Wash down twice
2) Stone Enzyme wash
Garments loading
↓
Water is added (1.6 Liter)
↓
Machine started running
↓
2.7 gm Neutral Enzyme added
↓
gm Anti back staining agent added
↓
1.08 Acetic acid added
↓
Steam to raise temp 45˚C
↓
Process time 20 minutes
↓
Drop liquor
3) Bleach wash
Water is added (1.6 Liter)
↓
Machine started running
↓
18 gm KMnO4 added
↓
Steam to raise temp 60˚C
↓
Process time 10 minutes
↓
Drop liquor
4) Neutralization
Water is added (1.8 Ltr)
↓
Machine started running
↓
Sodium Hyposulphite added
↓
1 Kg Salt added
↓
Steam to raise temp 50˚C
↓
Process time 10 minutes
↓
Check Shade
↓
Drop the liquor
5) Drying
Garments are then taken out
↓
Hydro extracted for 1.5 min
↓
Send to dryer for 20 minutes
A Leg panel was taken for this experiment which is 200 gram. At first, the leg panel was taken for desizing treatment then stone wash and acid wash is done. After washing and drying, various test is done. The process parameters are given below.
Process of Acid WashDesizing
Fabric weight: 0.2 kg;
Water: 2 liters;
Temperature: 60˚C;
Desizing agent: 2 gm;
Anti-Back staining agent: 2 gm;
Time: 20 min.
Stone wash
Water: 1.6 liters;
Temperature: 25˚C;
Metabisulphate: 8 gm;
Time: 5 min.
Acid Wash
Water: 0.26 ltr;
Acetic Acid: 26 gm;
potassium permanganate: 6.5 gm;
Thermocol balls are put into the washing machine;
Temperature: 25;
Time: 10 min.
After two rinse wash we do the neutralization process with sodium Meta bi sulfite. Then treated denim leg panels were rinsed two times.
Neutralization
Water: 1.6 liters;
Temperature: 25˚C;
Metabisulphate: 8 gm;
Time: 5 min.
Softener
Water: 1.4 liters;
Temperature: 25˚C;
Acetic Acid: 0.84 gm;
Softener: 1.4 gm;
Time: 5 min.
Hydro Extracting and Drying Processes
Extracting and Drying
Process flowchart of Acid Wash
Loading
↓
Desizing (If Necessary)
↓
Conditioning of the garments
↓
Stone Preparation
↓
Acid Wash
↓
Neutralization Of By-product (MNO2)
↓
Neutralization
↓
Finishing/Softening
↓
Drying.
A square of 10" × 10" is marked on the fabric samples using permanent marker before washing.
The length and width of the square are measured after washing.
Denim Fabric;
Knife;
Tear template;
Tear tester.
L-Histidine hydrochloride monohydrate: 0.5 g/L;
Di-sodium hydrogen orthophosphate di hydrate: 2.7 g/L;
Sodium chloride: 5 g/L;
Time: 4 hrs;
Temp: 37˚C.
Sample dimensions– 6" × 2".
Washing parameters:
Temperature: 49˚C;
Time: 45 min;
RPM: 40;
Steel Ball: 50 pcs;
Dia of steel ball: 6 mm.
Machine used—Mettler Toledo pH meter.
250 ml distilled water taken and boiled for 10 minutes. Then 10gm sample is cut in small pieces in 2 batches and added to the water one batch at a time and kept under water for 10 minutes. The temperature has to be moderate and the sample is cooled after taking out of the water.
Shrinkage percentage test report which is shown below in
Tearing Strength Test report which is shown below in
Colorfastness to Rubbing Test report which is shown below in
Colorfastness to wash test report which is shown below in
pH test report which is shown below in
| Wash type | Shrinkage percentage | |
|---|---|---|
| Length wise | Width wise | |
| Stone enzyme wash | 8% | 10% |
| Acid wash | 4% | 5% |
| Wash type | Tearing Strength Test | |
|---|---|---|
| Warp | Weft | |
| Stone enzyme wash | 49.6 | 24.6 |
| Acid wash | 56.4 | 29.2 |
| Wash type | Assessments | |||
|---|---|---|---|---|
| Grade for changing | Grade for staining | |||
| Dry | Wet | Dry | Wet | |
| Stone enzyme wash | 4/5 | 2 | 4/5 | 2 |
| Acid wash | ¾ | ½ | 3/4 | ½ |
From the shrinkage test done on 10" × 10" sample, it found out both lengthwise and widthwise shrinkage occurred in the fabric. But the stone enzyme wash shrinkage percentage is higher than the acid wash which is shown below in
Here the crock meter is used to test the rubbing fastness on the fabric in both dry and wet condition. During stone enzyme wash color fastness of rubbing very good in dry condition and fairly good in wet condition. During acid wash color
| Wash type | Assessments | ||||||
|---|---|---|---|---|---|---|---|
| Grade for changing | Color staining to multi-fibre fabric | ||||||
| Acetate | Cotton | Nylon | Polyester | Acrylic | Wool | ||
| Stone enzyme wash | 4/5 | 0 | 4 | 4 | 0 | 0 | 0 |
| Acid wash | 4/5 | 0 | 4/5 | 4/5 | 0 | 0 | 0 |
| Wash type | pH |
|---|---|
| Stone enzyme wash | 5.2 |
| Acid wash | 5.8 |
fastness of rubbing fairly good in dry condition and very poor in wet condition which are shown below in
Here checked both the warp way strength and weft way strength after wash. In warp way and weft way strength, acid wash sample higher than stone enzyme wash sample strength which are shown below in
After washing the leg panel under laboratory condition, we used the gray scale to measure the color fastness to wash where it scored 4.5 for stone enzyme and 4 for acid wash that means stone enzyme sample is very good and acid wash sample is good. That means, after both washing the leg panel shows considerable performance to color fastness to wash which are shown below in
We checked the pH of the leg panel surface using the pH meter and the result was slightly different for the two washes. But the variation was 0.6 and in both cases the fabric was slightly acidic at 2.2 and 2.8, which are shown below in
The aim of this project is to observe the impact of stone enzyme wash and acid wash on denim apparel characteristics. For that purpose, three same denim fabrics with twill 3/1 construction are made and after washing, changes in the characteristic of denim fabric have been observed. All washing treatments indicated
great influence on the tear strength, weight loss of fabric because of the variation of chemical, washing process, time, temperature and fabric.
Finally, in denim washing our country has a bright future due to wide spread market of denim garments. We need thorough knowledge of denim treatment process and also of the fashion going around the world. And this project will be a guideline for those who are interested in this sector. We believe that this project will be a guideline for the washing plants in understanding and doing various treatments.
In this paper, the impact of Stone Enzyme wash and Acid wash is observed. From this study, it is found that by the treatment of stone enzyme and acid the constructions of the garments are not changed a lot except GSM. On the other hand, although strength of the garments is reduced, it is within the acceptable range. Shrinkage of the garments does not exceed the required level after treatment. So stone enzyme and acid washing produce moderately aged looks of the garments as well as comfort.
The authors declare no conflicts of interest regarding the publication of this paper.
Jahan, T. and Khan, J. (2022) Impact of Stone Enzyme Wash and Acid Wash Based on Denim Garments. Journal of Textile Science and Technology, 8, 43-57. https://doi.org/10.4236/jtst.2022.81005