MINOR REPORT - To understand the behavior of strength and workability by cha...
final presentation
1. Influence of cold enzyme washing on physical
and mechanical properties of cotton-tencel
denim fabrics
…………………………….. ………………….............
Project supervision Submitted by
Prof Changhai Yi Rajib Chandra Gosh
武 汉 纺 织 大 学
……………………………………………………………………………
SCHOOL OF TEXTILE SCIENCE AND ENGINEERING
WUHAN TEXTILE UNIVERSITY
WUHAN,CHINA.
Year 2014-16
2. Introduction
• Research objective
The objective of the research, to get a good worn-look on cotton-tencel denim jeans
fabrics by cold enzyme washing and determine the change of physical and mechanical
properties of denim fabrics. By cold enzyme washing, denim jeans manufacturers
could be saved time and temperature as well as increased production.
• Research outline
1. Literature review of cold enzyme
2. Literature review of cotton-tencel denim fabrics
3. Cold enzyme treatment of cotton-tencel denim fabrics
4. Evaluation of physical & mechanical characteristics
• Practical relevance
If denim jeans manufacturers used cold enzyme instead of conventional enzyme for
washing of jeans, they would be got a better advantages then conventional enzyme
washing. So in practical , it is very useful for denim jeans washing.
3. Literature review
Introduction
In order to carry the experiment of cold enzyme denim washing , evaluated of cotton-
tencel denim fabric and analysis of the data more effective , literature review was
done. Fundamental understanding the about the cotton-tencel denim fabric include
the material, cold enzyme wash and the enzyme treatments also introduce.
Concept:
• Characteristics of tencel
• Cotton-tencel denim fabric
• Cold enzyme
• Cold enzyme treatment
• Customers aspects for cotton-tencel denim fabrics of jeans.
4. Experimental
• Cold enzyme used
Cold enzyme was provided by DENMARK .
According to DENMARK company , the working condition is –
Enzyme = 1.5-2 g/l
Liquor ratio = 1:15
Temperature = 20-35°C
Time = 15-20 minute
pH = 4-4.5
• Fabrics used
Composition of 84% cotton and 16% tencel blue denim fabric were used.
Fabric count was 21S ×16S. The fabric GSM was 7.4-7.5oz , 3/1 right twill.
Fabric density was 130× 66 and fabric width was 149-150 cm. Fabric’s weft
shrinkage 1-2%. For this experiment denim fabrics were brought from Hubei
Chengui Shunfu Textile & Garment Co. Ltd.
5. Experimental
• Equipment
For enzyme washing of denim fabrics, Garment Dyeing Washing
machine Intelligence ( QIBO, China) was used. It is one kind of
front loading washing machine where liquor ratio was 1:15.
Figure 1 Garment Dyeing Washing machine Figure 2 Loading of Denim fabrics
6. Experimental
• Treatment procedure( Time as a variable)
Table 1 Working condition of cold enzyme washing
Sample Time(minute) Temperature(°C) Cold enzyme (%)
1 20 34
1.52 18 32
3 15 29
4 10 28
Figure 3 Drying of cotton-tencel denim fabrics after cold enzyme washing
7. Experimental
• Flow chart of denim washing by cold enzyme :
Desizing (H2O2= 1.5 g/l)
Rinse wash( 5 minute)
Cold enzyme washing( 20-35°C, 10/15/18/20 min)
Rinse wash ( 5minute × 2)
Clean up ( 5 minute,60°c)
Rinse ( 5minute)
Drain
For clean up process , H2O2 = 0.7g/l and detergent =0.3 g/l were used. Then rinse
was given. After washing by cold enzyme, denim fabrics were dried at room
temperature.
8. Result and discussion
• Change in color fastness to rubbing
• Scanning electron microscopy
• Change in air permeability and thickness
• Change in GSM & fabric weight
• Change in tensile strength
• k/s value
• Change in Tearing strength
• Change in pilling property
• Change in crease recovery
• Change in wick ability
• Determination of static electricity
• Determination of FTIR
9. Change in Color fastness to rubbing
After cold enzyme washing, unfixed dyes were removed from surface of yarn.
As a result , rubbing fastness( dry and wet) were improved.
A(dry) -- B(wet) -- C(dry) -- D(wet)
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
sample 1
Fair
Good
poor
Moderate
Washing stage
Rubbingfastnessgrading
A,B= Before wash
C,D= After cold enzyme wash
Figure 6 sample 1 (20 Minute) rubbing fastness grading
A(dry) -- B(wet) -- C(dry) -- D(wet)
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
Moderate
Fair
sample 2
poor
Moderate
Washing stage
Rubbingfastnessgrading
A,B= Before wash
C,D= After cold enzyme wash
Figure 7 sample 2 (18 minute) rubbing fastness grading
A(dry) -- B(wet) -- C(dry) -- D(wet)
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
Moderate
Fair
sample 3
poor
Moderate
Washing stage
Rubbingfastnessgrading
A,B= Before wash
C,D= After cold enzyme wash
Figure 8 sample 3 (15 minute) rubbing fastness grading
A(dry) -- B(wet) -- C(dry) -- D(wet)
0.0
0.5
1.0
1.5
2.0
2.5
3.0
slightly fair
Moderate
poor
Moderate
Washing stage
Rubbingfastnessgrading
sample 4
A,B= Before wash
C,D= After cold enzyme wash
Figure 9 sample 4 (10 minute) rubbing fastness grading
10. Scanning electron microscope
The SEM results showed the presence of sizing
materials present on the surface of the
untreated samples.
Figure 10 (a) Before sample Figure 10 (b) Before sample
11. Scanning electron microscope
Figure After desizing samples was shown that there had
hairiness and unfixed dyes which was clearly visible. It
was responsible for poor rubbing fastness(dry and wet)
and also decreased tensile strength as well as different
properities of denim fabrics.
Figure 11 After desizing samples Figure 12 After desizing samples
12. Scanning electron microscope
Figure 13 After cold enzyme washing sample 1 Figure 14 After cold enzyme washing sample 2
Figure 15 After cold enzyme washing sample 3
Figure 16 After cold enzyme washing sample 4
13. Change in air permeability and thickness
It was shown that if thickness is higher, air permeability is lower.
On the other hand, thickness of denim fabrics is lower, air
permeability is higher.
Table 2 Determination of air permeability & thickness
samples Before wash After cold enzyme wash
Thickness(m
m)
Air
permeability
(mm/s)
Thickness(mm
)
Air
permeability
(mm/s)
S-1 0.46 41.09 0.56 35.95
S-2 0.48 41.00 0.55 34.25
S-3 0.48 41.05 0.55 32.75
S-4 0.47 41.08 0.59 35.07
14. Change in GSM & Fabric weight
• Determination of fabric weight loss
Samples no Before wash
(gm.)
After
wash(gm.)
Weight loss%
Sample 1 267 266 -0.4%
Sample 2 274 273 -0.3%
Sample 3 247 245 -0.8%
Sample 4 254 252 -0.8%
15. Change in GSM & Fabric weight
• Determination of fabric GSM
Cotton fabrics were applied to considerable tensions during weaving. In calendaring
this stretch was enhanced and temporarily set in the fabric . It is called relaxation
shrinkage. Relaxation shrinkage is usually greater in the warp direction . Due to this
fabric GSM is increased.
B S-1 S-2 S-3 S-4
0
1
2
3
4
5
6
7
8
FabricGSM(OZ/yd
2
)
Samples of washing
After wash=S-1,S-2,S-3,S-4
Before wash=B
Figure 17 Determination of fabric GSM
16. Change in tensile strength
Table 4 Determination of tensile strength
Samples
no
Before wash After cold enzyme
wash
Warp(N) Weft(N) Warp(N) Weft(N)
S-1 1160 740 1284 886
S-2 1159 741 1280 851
S-3 1161 739 1271 860
S-4 1160 742 1276 853
17. Change in K/S value
Table 5 Determination of K/S value
Samples After ( cold
enzyme wash)
Before wash
1 16.018 16.599
2 16.301 16.888
3 16.400 16.522
4 16.428 16.578
22. Determination of Static electricity
Table 10 Measurement of static electricity
Sample Potential
voltage (V)
Time(S) Potential
voltage (V)
Time(S
)
Warp direction Weft direction
Before 325 0.31 274 0.34
S-4 336 0.40 237 0.22
S-3 315 0.29 225 0.11
S-2 281 0.28 181 0.23
S-1 263 0.19 266 0.37
23. Determination of FTIR characteristics
0 1000 2000 3000 4000 5000
0.00
0.01
0.02
0.03
0.04
0.05
0.06
0.07
0.08
2673.26771
1299.98733
3743.73205
2025.20281
Before wash
Absorbance
Wavenumbers(cm
-1
)
Figure 28 FTIR Characteristics of sample 1Figure 27 FTIR Characteristics of before wash
Figure 29 FTIR Characteristics of sample 2 Figure 30 FTIR Characteristics of sample 3 Figure 31 FTIR Characteristics of sample 4
24. Conclusion
Conclusion
• It was observed that after cold enzyme wash, there
was a little change in weight loss and fabric GSM.In
this experiment, color fastness to rubbing ( dry &
wet) was improved. From observation of SEM , it
was cleared that there was less hairiness and no
unfixed dyes on surface of cotton- tencel denim
fabrics after cold enzyme washing. So that rubbing
property of denim fabrics was improved.
• The tensile strength of these samples became
stronger in both fabric directions. As well as tearing
strength of cotton- tencel denim fabrics was also
improved .
25. Conclusion
• Wicking property of cotton- tencel denim fabrics
was improved due to good absorbency of tencel
yarn.
• Due to removal of hairiness of denim fabrics,
pilling property of denim fabrics was improved
after denim fabrics.
• After cold enzyme washing, unfixed dyes was
removed from surface of cotton- tencel denim
fabrics. So that K/S value was decreased. That’s
means color fading was occurred.
• In this experiment, crease recovery of denim
fabrics also was improved after cold enzyme
wash.
26. conclusion
• After cold enzyme wash, air permeability of cotton-
tencel denim fabrics was decreased. Thickness of
denim fabrics was increased due to compact formation
of denim fabrics after cold enzyme washing.
• Static electricity of cotton- tencel denim fabrics was
also increased after cold enzyme washing but this value
of static charge is comfortable for human skin feel.
• So that it is observed that after cold enzyme wash,
mechanical and physical properties of cotton- tencel
denim fabrics were improved.
