Denim washing process and value addition by different process

Final Year Project Denim wash
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Bangabandhu Textile Engineering college
University of Dhaka
DENIM WASHING PROCESS AND VALUE ADDITION BY
DIFFERENT PROCESS
A PROJECT REPORT
Submitted by
SAJIB CHAKMA (ROLL-72), MD. ALAMIN (ROLL-35),
MD. AL-AMIN (ROLL-13), TOFAYEL AHAMMED (ROLL-05),
MD. FARUK HOSSAIN (01)
In partial fulfillment for the award of the degree
Of
BACHELOR OF SCIENCE in TEXTILE ENGINEERING
DEPARTMENT OF FABRIC MANUFACTURING
BANGABANDHU TEXTILE ENGINEERING COLLEGE
KALIHATI, TANGAIL.
UNIVERSITY OF DHAKA
1st
JANUARY to 28th
FEBRUARY in 2018

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DEPARTMENT OF TEXTILE ENGINEERING
BANGABANDHU TEXTILE ENGINEERING COLLEGE
KALIHATI, TANGAIL.
BONAFIDE CERTIFICATE
Certified that this project report “DENIM WASHING PROCESS AND VALUE
ADDITION BY DIFFERENT PROCESS” is Bonafide work of “SAJIB CHAKMA, MD.
ALAMIN, MD. AL-AMIN, TOFAYEL AHAMMED, MD. FARUK HOSSAIN” who
carried out the project work under my supervision. This is to further certify to the best of
my knowledge that this project has not been carried out earlier in this college and the
University.
SIGNATURE SIGNATURE
CO- SUPERVISOR SUPERVISOR
MD. SAIFUL ISLAM TAPOSH KUMER PAUL
FOREMAN SUPERINTEADENT
BTEC, KALIHATI, TANGAIL. TVI, KALIHATI, TANGAIL.

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ACKNOWLEDGEMENT
All pleasure goes to the Almighty to give me strength and ability to complete my two months long project
work and submitted a project work report at Bangabandhu Textile Engineering College and the help of
practical field Fakhruddin Textile Mills Ltd. It was a great opportunity for me to complete the project
work with the assistance of persons employed in Fakhruddin Textile Mills Limited.
I feel grateful to my academic co-supervisor Md. Saiful Islam Lecturer, Bangabandhu Textile Engineering College
as well as Suman Nandy my factory supervisor, Md. Asraful Alam, senior manager of Dyeing section for their
continuously guiding me about the development and preparation of this project report. They have enriched me with
sharing necessary theoretical and practical ideas and supervised me to complete this report on time.
I would like to express my thanks to Eng. Abdul Majid Principle, Bangabandhu Textile Engineering
College. For his kind help to finish my project work report. I would like to express my thanks to Eng.
Md. Ismail Molla; Principle, Chittagong Textile Engineering College, for providing me necessary
information to complete the report.
I am also grateful to the supervisors, technicians, operators and all other staffs of Fakhruddin Textile
Mills Ltd. who were most cordial and helpful to us during the tenure of internship.
Finally, I would like to express a sense of gratitude to my beloved parents and friends for their mental
support, strength and assistance throughout writing the training report.

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ABSTRACT
Effect of various washing process on the properties of indigo dyed four-way stretch denim fabric
was studied in this research. The different washing techniques (Dark wash enzymatic treatment, Medium
wash- enzymatic treatment with pumice stone, Bleach wash- enzymatic treatment with bleaching powder
and pumice stone, Acid Wash-Enzymatic treatment with potassium permanganate and pumice stone) were
applied on the fabric. Properties of four-way stretch denim fabric like tear strength, dimensional stability
to washing, color fastness to washing, color fastness to water, color fastness to perspiration, color fastness
to light, color fastness to ozone, color fastness to rubbing, fabric weight were investigated and compared
with each other before and after washing process. All tests were carried out according to the ISO standards.
Pollution load of washing effluent of different washing techniques were also evaluated to measure their
impact on the environment. The surface analysis of the different washed fabric was examined by scanning
electron microscope (SEM). From the result was examined then the best result observed in the fabric of
medium wash in terms physic mechanical properties, chemical properties, pollution load of washing
effluent, cost comparison, morphological changes of fabric surface. The results indicated that the durable
and sustainable wash process for four-way stretch denim fabric is medium wash (enzymatic treatment
with pumice stone).

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CONTENT
SL No DETAILS Page no
01 1. DENIM
02 1.1 Definition 7
03 1.2 Background 8
04 1.3 Flowchart of denim washing 10
05 2. DENIM WASH
06 2.1 Types of denim wash 11
07 2.2 Random bleach wash for denim 13
08 2.3 Types of chemical use in washing plant 16
09 2.4 Characteristics of denim fabric 16
10 2.5 Types of machine used in washing plant 17
11 3. INDIGO DYE
12 3.1 Indigo background 18
13 3.2 Denim fabric process 18
14 3.3 Reaction of indigo dye 19
15 4. DENIM WASHING PROCESS
16 4.1 Denim garment washing 20
17 4.2 Types of denim wash process 20
18 4.3 Types of wet wash process 21
19 4.4 Denim bleach 22
20 4.5 Denim bleach bleaching washing 23
21 5. ENZYME 28
22 5.1 Objectives 24
23 5.2 Types of Enzyme 24
24 5.3 Enzyme wash 25
25 5.4 Acid wash 25
26 5.5 Stone wash 26

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27 5.6 Limitation of stone washing 27
28 5.7 Other washing 28
29 5.7.1 Rinse wash 28
30 5.7.2 Acid wash 29
31 6. HAND WHISKER 30
32 6.1 Grinding 31
33 6.2 Pattern making 31
34 6.3 Padding 31
35 6.4 Hand grinding 31
36 6.5 Wheel grinding 32
37 6.6 Tagging 32
38 6.7 Area of application 33
39 6.7.1 Clipping 33
40 6.7.2 Wet process 33
41 6.7.3 Pre treatment 34
42 7. TYPES OF DENIM WASH 35
43 7.1 Chemical wash & Denim bleach 35
44 7.2 Limitation 36
45 7.3 Random bleach 37
46 7.4 Enzyme wash 38
47 7.4.1 Acid wash 40
48 7.4.2 Tinting 42
49 8. MECHANICAL WASH 44
50 8.1 Stone wash 44
51 9. SOFTENING PROCESS 50
52 9.1 Chemical on denim 51
53 9.2 Machine use for denim washing 52
54 10.VALUE ADDITION 55
55 10.1 Overview; Global Textile clothing industry 56
56 10.2 Value addition by different process 57
57 11.FINDDING 59
58 12.CONCLUSION 60
59 13. RECOMMENDATIONS 61
60 14. REFERENCES 61

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CHAPTER-1
 DENIM
1.1 Introduction:
Denim is the oldest, most widely used, most fashionable and most versatile fabric of the world. At
present denim is mainly used for producing garments particularly trousers for the young people. The gross
production of denim fabric is approximately 3,000 million meters per year.
Denims are produced from 4 oz. to 16 oz. / sq. yds. In weight. Technically Denim is defined as a
3/1 warp faced twill but also produced from weaves like: Left hand twill, right hand twill, broken twill,
cross hatches, cords, dobby's, structures, etc. .
Denims are made from yarn dyed warp and undyed weft. Traditionally, denim was dyed with
various shades of indigo, yarn-dyed, different costs, and over-dyed with various types finishes at fabric as
well as garments state. Denims are manufactured different types of after treatments or washes like stone
wash, bleach wash, hand wash, acid wash, over dyed, printed denims and even embossed.
Denim fabrics are used as jeans trousers both for men and ladies. It is extensively used in the world
as casual garments, Shirts, jackets, children wears are also made of denim fabrics. Its versatility, finds
applications in furniture upholstery, bed covers, curtains, etc. Denim now-a-days is a very demandable
product. To make a denim fabric the required yarn for the definite construction should be dyed then make
a weavers beam to go to weaving to make fabric.
Denim washing is the aesthetic finish, which is given to the denim fabric to enhance the appeal
and to provide strength. In case of denim washing, several wash effects can be produced such as- color
fading with or without patchiness, seam puckering, de-pilling, crinkles, hairiness etc. But denim washing
follows a process flow-chart, by which all the mentioned effects can be achieved easily.

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1.2 BACKGROUND:
Ever since the inception of "blue jeans" in the 1870s as work wear for miners and cowboys, these
iconic garments have evolved to become a popular item of casual wear throughout the world today.
Coming in various fits to suit different tastes and fashions an important part of their appeal is the
distressed look, visibly aged and worn, but still intact and functional. The process of washing improves
the fastness properties of indigo-dyed denim Jeanswear and in addition by altering the types of washes,
various fashion looks are achieved.
In this technical bulletin we will explain how denim apparel is wet processed and highlight the
parameters associated which need to be controlled in denim manufacturing and subsequent wash
processes. The "wash down" and other "post make" processes applied to denim garments are many and
varied. Often the objective is to distress the garment so that it looks old and worn. This distressing gives
the garments a "fashion" appeal and also softens an otherwise harsh fabric. These "post make" process
can have a devastating effect on the sewing threads and therefore the seams, if care is not taken in their
selection and application. After wash / post processing repair rates can be very high with harsh wash
down treatments and 40% repair levels are not uncommon.
We highlight the Coats range of sewing threads that have been designed specifically to withstand
the rigors of denim wet processing and which in addition can add a fashion element of their own through
contrast colors and other decorative applications. For example, core spun threads such as Coats Epic and
Dual Duty offer excellent all round sewing performance due to their construction and specially
formulated lubrication. The high tenacity filament core provides the toughness for the majority of the
most punishing applications. The cotton wrap of Dual Duty allows its color to fade with the fabric whilst
the polyester wrap of Epic retains more of its original color.

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1.3 Flowchart of Denim Washing:
Garments Received
↓
Dry Process
↓
Send to Wet Process
↓
Garments Loading in Washing Machine
↓
De-Size
↓
Enzyme
↓
Bleaching (If needed)
↓
Neutralization
↓
Extracting
↓
Drying
↓
P.P spray
↓
Neutralization
↓
Tinting
↓
Softener
↓
Extracting
↓
Drying
↓
3D
↓
Curing
↓
Q.C check
↓
Delivery

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CHAPTER-2
 DENIM WASH:
Now-a-days denim wash is much popular both dry and wet washing process. According to the fashion
and appearance, there include new washing process and technology such as 3D or laser techniques. In
denim washing is done to produce effects like color fading with or without patchiness, crinkles, seam
puckering, hairiness, Pilling softened-hand feel, stabilized dimension etc. Most of the denim wash effect
vintage look. Now I want to describe briefly denim washing types with flow chart.
2.1 Types of Denim Wash:
Different types of denim wash are as follows-
1. Rinse Wash
2. Enzyme wash
3. Stone wash
4. Caustic wash
5. Acid wash
6. Random bleach wash
7. Ice-or Snow was

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8. Tinting
9. Net bleach
10. Resin wash
11. Milk wash
12. Cold Pigment wash

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2.2 Random Bleach Wash for Denim:
Here we try to show a common use wash in garments industry which is random bleach wash. The recipe
and process sequence of R.B wash is as follows-
Random Bleach Wash Effect (Front Side)

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Random Bleach Wash Effect (Back Side)
Recipe:
1. TA – Super ⇒ 100 gm
DP-7 ⇒ 50 gm
Stone ⇒ 5 Kg
2. Bleach:
K.C.I bleach ⇒100 gm
3. Neutral:

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Metal ⇒200 gm
4. Random Process:
Potassium Per manganite ⇒ 30 gm
Water ⇒ 2 Liter
Fume ⇒ 100 Pcs
5. Note:
Garment should be turn-inside.
1. Neutral:
Meta ⇒ 500 gm
7. P Spray:
Potassium per manganite ⇒ 1.15 gm
Neutral:
Meta ⇒100 gm
Wash ⇒ H/C
8. Clean:
Caustic ⇒ 300 gm
Dp-7 ⇒ 100 gm
Blue Brightener ⇒ 50 gm

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9. Softener ⇒ 100 gm
Silicon ⇒ 100 gm
2.3 Types of chemical used in washing plant:
1. Enzyme 2. Detergent
3. Acetic Acid 4. Anti-stain
5.Bleaching powder 6.Sodium hyposulfite
7. Caustic Soda 8. Soda Ash
9. Sodium Bicarbonate 10. potassium Permanganate
11. cationic/nonionic Flax softener 12. Micro Emulsion Silicon
13. Salt (sodium chloride) 14. Buffer
15. Hydrogen peroxide 16. Stabilizer
17. Fixing 18. Catanzaro
19. Optical Brightener 20. Resin
21. Sodium Metabisulphite 22. Desiring agent
2.4 Characteristics of Denim Fabric:
 It is for long wearing.
 It is hard wearing.
 It is very strong and durable.
 It resists snags and tears
 It creases easily.

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2.5 Types of machine used in washing plant:
 Sample washing Machine (Horizontal / Vertical Type)
 Washing Machine (Side loading)
 Washing Machine (Front loading)
 Hydro extractor Machine
 Dryer Machine (Steam)
 Dryer Machine (Gas)
 Chemical Mixture Machine
 Industrial Oven (Gas/Electric)
 Boiler
 Submersible Pump
 Grinding Machine
 Tagging Machine
 Steam chamber for crinkle
 E.T.P (Effluent Treatment Plant)
 Generator
 Sand Blasting Gun
 Sand Blasting chamber
 Spray gun and dummy

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CHAPTER-3
 INDIGO DYE
3.1 Indigo Background:
Indigo, or indigo tin, is a dyestuff originally extracted from the varieties of the indigo and wood
plants. Indigo was known throughout the ancient world for its ability to color fabrics a deep blue. Egyptian
artifacts suggest that indigo was employed as early as 1600 B.C. and it has been found in Africa, India,
Indonesia, and China.
The dye imparts a brilliant blue hue to fabric. In the dying process, cotton and linen threads are
usually soaked and dried 15-20 times. By comparison, silk threads must be died over 40 times. After
dying, the yarn may be sun dried to deepen the color. Indigo is unique in its ability to impart surface color
while only partially penetrating fibers. When yarn died with indigo is untwisted, it can be seen that the
inner layers remain uncolored. The dye also fades to give a characteristic womb look and for this reason
it is commonly used to color denim. Originally extracted from plants, today indigo is synthetically
produced on an industrial scale. It is most commonly sold as either a 100% powder or as a 20% solution
3.2 Denim fabric process:-
Desiring → Enzyme → Caustic → bleaching → Hypo → Softening → Hydro extractor→ Dryer m/c →
Garments Delivery.

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3.3 Reaction of Indigo dye:

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CHAPTER-4
 DENIM WASHING PROCESS
4.1 Denim garments washing:
The technology which is used to modify the appearance, outlook comfort ability & fashion of the
garments is called garment washing. Since 1978, garments pre washing has become more and more
popular. It began with denim jeans for the following reasons, 1.Before garments pre washing was done
on jeans, consumers had to wash them at home before wearing them because before washing they were
too stiff, too long and too big to wear. 2. After pre washing, the consumers do not have to worry about
the fit after they wash them as pre washing has taken away almost all the shrinkage and made the jeans
stable. 3. After pre washing the denim color looks livelier particular with the pronounced washed look
left on the double needled seams.
4.2 Types of Denim wash process:
Mechanical washes
1.Stone wash
2.Micro-sanding
Chemical washes
1.Denim bleaching
2.Enzyme wash
3.Acid wash

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4.3 TYPES OF WET WASH PROCESS:
1. Normal wash/ garments wash/ rinse wash. 2. Pigment wash.3. Caustic wash.4. Silicon wash.
5. Stone wash.6. Enzyme wash.7. Stone Enzyme wash.8. Acid wash.9. Bleach wash.10. Tinting wash
TYPES OF DRY WASH PROCESS:
1.Sand Blasting.2. Hands scraping.3. Over all wrinkles.4. Permanent wrinkle.5. Grinding &Destroy.6.
Broken & tagging.7. PP Spray & PP Sponging.8. Etc.

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4.4 DENIM BLEACH
Denim bleach in this process a strong oxidative bleaching agent such as sodium hypochlorite or
KMnO4 is added during the washing with or without stone addition. Discoloration produced is usually
more apparent depending on strength of the bleach liquor quantity, temperature and treatment time. It is
preferable to have strong bleach with short treatment time. Care should be taken for the bleached goods
so that they should be adequately antichlor or after washed with peroxide to minimize yellowing. Materials
should be carefully sorted before processing for color uniformity.

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4.5Denim bleach bleaching washing:
This way be considered as a preparatory process of mercerizing, dyeing, or printing .therefore
proper bleaching should be carried out other wish the subsequent process would be fault.
Objective:
1.To remove the size material from the garments.
2. To remove the starch present on the garments.
3. for soft feeling to wear the garments.
4. To increase the color fastness and rubbing fastness.
5. Especially develop the “Bio-polishing’’ affect cotton/Denim.
6. Enzyme improves the anti-pilling properties.
7. Enzyme attacks more the surface of the fabrics and gives a very smooth surface.

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CHAPTER-5
 ENZYME
Enzymes are proteins Bio catalyze. It has huge life cell .The cell is the basic structural and functional
unit of all known living organisms. It is the smallest unit of life that is classified as a living thing, and is
often called the building block of life. Some organisms, such as most bacteria, are unicellular (consist of
a single cell). Other organisms, such as humans, are multicellular. (Humans have an estimated 100 trillion
or 1014 cells; a typical cell size is 10 μm ; a typical cell mass is 1 monogram.) The largest known cell is
an unfertilized ostrich egg cell. In enzymatic reactions, the molecules at the beginning of the process are
called substrates, and the enzyme converts them into different molecules, called the products. Almost all
processes in a biological cell need enzymes to occur at significant rates. Since enzymes are selective for
their substrates and speed up only a few reactions from among many possibilities, the set of enzymes made
in a cell determines which metabolic pathways occur in that cell.
5.1 Objectives:
1.To remove the size material from the garments.
2. To remove the starch present on the garments.
3. for soft feeling to wear the garments.
4. To increase the color fastness and rubbing fastness.
5. Especially develop the “Bio-polishing’’ affect cotton/Denim.
6. Enzyme improves the anti-pilling properties.
7. Enzyme attacks more the surface of the fabrics and gives a very smooth surface.
5.2 Types of Enzyme:
Mainly two types of Enzyme:
1. Acid Enzyme (a. Powder b. Liquid form.)
2. Neutral Enzyme (a. Powder b. Liquid form.)
After enzyme washing us get these change:
# Color
# GSM decrease

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# Softener
# Strength
5.3 Enzyme wash:
it is environmentally friendly wash. It involves the Application of organic enzymes that eat away at the
fabric, i.e. the cellulose. When the desired color is achieved, the enzymes can be stopped by changing
the alkalinity of the bath or its temperature. Post treatment includes final rinsing and softening cycle.
The effects produced by the cellulose enzyme are –
# Use of cellulose making the seams, hems, and pockets more noticeable
# Salt pepper effect is color contrast effect.
# faded garment with acid cellulose enzyme provides less color contrast in proportion to garment
washed with neutral cellulose enzymes.
Garment load size of the machine is 35-40 jeans per machine and it cannot be overloaded.
5.4 Acid wash:
It is done by tumbling the garments with pumice stones presoaked in a solution of sodium hypochlorite
or potassium permanganate for localized bleaching resulting in a non-uniform sharp blue/white contrast.
In this wash the color contrast of the denim fabric can be enhanced by optical brightening. The
advantage of this process is that it saves water as addition of water is not required.

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5.5 Stone wash:
In the process of stone washing, freshly dyed jeans are loaded into large washing machines and
tumbled with pumice stones to achieve a soft hand and desirable look. Variations in composition,
hardness, size shape and porosity make these stones multifunctional. The process is quite expensive and
requires high capital investment. Pumice stones give the additional effect of a faded or worn look as it
abrades the surface of the jeans like sandpaper, removing some dye particles from the surfaces of the
yarn.

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5.6 Limitation of stone washing:
# Quality of the abrasion process is difficult to control Outcome of a load of jeans is never uniform, little
percentage always getting ruined by too much abrasion.
# the process is non-selective.
# Metal buttons and rivets on the jeans in the washing machines get abraded.
# This reduces quality of the products and life of equipment, and increases production costs.
# Stones may turn into powder during the process of making the garment grayish in color and rough too
# Provides rougher feel than enzyme wash
# Stone may lead the harm to the machine parts
MICRO-SANDING
There are 3 ways for this technique:
# Sandblasting
# Machine sanding
# Hand sanding or hand brushing

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5.7 Other washing:
5.7.1Rinse wash:
1.Chemically bleaching jeans so that the color fades away
2.Breaks down the fibers of jeans and creates white streaks or spots on denim
3.Gives a unique rugged look, also called snow wash
4.Earlier involved the use of pumice stone
5.Presently process involves spraying chemical and removing it immediately
6.Come in colors like blue, black, green, brown, grey etc.
Cellulose wash
7. This is done to achieve a wash down appearance without the use of stones or with reduced quantities
of stones.
8. Cellulose enzymes are selective only to the cellulose and will not degrade starch.
9. Under certain conditions, their ability to react with cellulose (cotton) will result in surface fiber
removal (weight loss).
10. This will give the garments a washed appearance and soft hand.
Ozone fading
11.By using this technique, the garment can be bleached.
12.Bleaching of denim garment is done in washing machine with ozone dissolved in water.
13. Denim garments can also be bleached or faded by using ozone gas in closed chamber.
14. In the presence of UV light, there is an interaction between the hydrocarbons, oxides of nitrogen and
oxygen that causes release of ozone.

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5.7.2 Acid wash:
Acid washing or ice washing is usually done by dry
Tumbling the garments with pumice stones presoaked in
An acid solution, such that
Localized bleaching is
Effected in a non-uniform
Sharp blue / white contrast
In the garment.

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CHAPTER-6
 HAND WHISKER:
In this process the same machine is use as used in brushing. On Denim, whiskers Chevrons are nothing
but the worn out lines / impression generated by natural wearing on hip & thigh area. There are many
designs & pattern available. This is being done manually with help of sharp edge Emery paper rolled on
fine wood stick or pasted on plastic material. Before starting execution placements & pattern
must be marked on garments, this will help operator to execute the pattern right to match theaesthetics of
garment. Hot spots are heavy/intense area on thigh or knee which is made purposely to create used look &
on knee area if any whiskers line are there, called knee star.

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6.1 Grinding:
Edge distressing or grinding is the process of destruction on jeans form edges of the garment.
When we look at old jeans we find it destroyed from the edges of pockets, fly area, belt and bottom.
This used effect can be created on jeans by grinding and is of key importance in high fashion garments.
It include the following processes.
6.2 Pattern making:
In grinding first the pattern is make of different designs then these pattern is mark on the
grinding areas in the garment with the help of chalk. By doing all these the grinding area on the garment
is become visible.
6.3Padding:
This is the main process of grinding in which fabric is put on the plate, which have rubber pad of
same pattern or design which is already mark on the garment .then
emery paper is rubbed against the garment which remove the yarn from the garment to get the desire
effect. 100 grade of emery paper is use for this process.
6.4 Hand grinding:
This is the process in which garment is slightly damage by removing surface yarn with the help
of hand grinding machine. Hand grinding is done on the small areas while padding is done on
large areas. The effect of both process (Padding and hand grinding)
Are approximately same. Grinding is done of garments by pen type of stone tools. It can be done
in mid of the wash process. In many workshops it is done before any wash process as first process after
Stitching. Stone tools similar to grinders used in wood and stone industry are utilized to work on garments
with a few amendments to their design. Pen type tools are very affective for this art work but consistency
is always a big question while dealing in production. They are not much effective in large quantity
production units. Staff is to be very experienced and careful otherwise it may damage the

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garment beyond requirement. To work on edges is very sensitive and any heavy destruction willopen the
edges and make the garment not to wearable. This aspect needs special care and supervision in industry.
6.5 Wheel grinding:
In this process the edges of the garment like edges of the waist band, bottom hem, front pocket,
back pocket and back pocket cover are grind using wheel grinding machine. In high production units it is
usually done with fixed grinding machines where grinding stone wheals fixed on high speed electrical
motors. Operators rub the edges to rotating stone wheal to get the effect. Again the risk of damage to
extent where the edges get open is there and to avoid it strict supervision and skilled staff is of key
importance. This method is very time and cost effective and large quantities are always deal in this way.
6.6 Tagging:
Tacking or more commonly tag pinning is a very in fashion style in denim garment in these days.
Usually tag pin machines are used to attach tag pins to garment. The procedure is very simple and
proceeds as; garment is folded on required area and tacked
Through folds. Garment is folded on specified areas and the fold is locked by tag
pins. Now the garment is processed in washer and a permanent fold appears after removal of tag pin. This
is important that tag pin is removed when the garment is dried completely. The inner of the fold is dark in
shade due to less exposure to mechanical rubbing and chemicals.

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6.7 Area of Application:
This effect can be designed anywhere on the garment in different styles. Most favorite areas for
tacking are on waistband, bottom hems, back pocket and front pocket cornered Tag Pin Tagging Machine
6.7.1 Clipping:
In this process the small areas of the garment is bound by using clips on the required areas
(generally at the bottom hem) then garment is put in the oven and finally forward to the washing dept. for
final effect.
6.7.2 Wet process:
It is called wet process because in this we use certain chemical to obtain a desired result.
1. Pre-Treatment
2. Washing
3. Enzyme wash
4. Bleach wash
5. Stone wash
6. Sand blasting
7. Tinting
8. Over dyeing
9. Spraying
10. Whiskering

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6.7.3 Pre-treatment:
This is very first & basic step but most important step of washing. Here the fate of denim garment
is decided that it’s going to appear good or bad.
Good Pretreatments avoid streaking, stiffness & color loss. This process removes impurities, starch
& stains during handling of fabric. This step is also called desiring (Removal of Size applied during denim
fabric making in weft yarn). All the woven fabric contains size on them due to reasons to strengthen the
yarn for weaving. There are many types of sizes available in the market but they can be divided in two
major groups.
1. Water Soluble (CMC or PVA based sizes) and
2. Dissolvable sizes in water (Starch based). Starch based sizes are most commonly used due to
cheap prices & readily availability.

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CHAPTER-7
 TYPES OF DENIM WASH:
7.1 Chemical wash:
-Denim bleaching
-Enzyme wash
-Acid wash
-Tinting
-Over dyeing
Denim bleach:
This is one an important step in washing denim & can be done by various bleaching agents.
a) Calcium hypo chlorite
b) Sodium hypo chlorite
c) Hydrogen per oxide
d) Potassium permanganate
First two chemicals are commonly being used for every medium to vintage denim but when it comes
to super vintage & light shade it’s advisable to use potassium permanganate bleach to cut the color faster
till half way & then neutralize it & go with Liquid ( Hypo ) bleach to adjust the desired shade. This process
helps to get Greyer cast& also protects the lycra or spandex, retain elasticity. Hydrogen Peroxide is rarely
used as bleaching agent when very less color loss required or if fabric is sculpture top. As it takes longer
time to give desired effect. Potassium Permanganate is also being used on 100% sulphur black
denim fabric for bleaching or reducing agent to get unique effects. As its not production friendly till
laundry has very expertise team to handle this program, otherwise it will result in many shades &cast.

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Proper Neutralizations of bleaching process is very essential in order to get rid of fabric strength, bad
smell from garment, yellowing & skin irritation etc. In this process a strong oxidative bleaching agent
such as sodium hypochlorite or KMnO4 is added during the washing with or without stone addition.
7.2 Limitation:
 Process is difficult to control i.e. difficult to reach the same level of bleaching in repeated runs.
 When desired level of bleaching reached the time span available to stop the bleaching is very
narrow. Due to harshness of chemical, it may cause damage to cellulose resulting in severe
strength losses and/or breaks or pinholes at these am, pocket, etc.
 Harmful to human health and causes corrosion to stainless steel.
 Required antichlor treatment.
 Problem of yellowing is very frequent due to residual chlorine.

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 Chlorinated organic substances occur as abundant products in bleaching, and pass into the
effluent where they cause severe environmental pollution
7.3 Random bleach:
It is an uneven effect, sometime also known as cloudy effect. In which
denimis bleached indirectly via towel piece or cotton balls it produce more merge and cloudyeffect cotton
ball is more successful but cotton towel are some tome used to produce cloudier effect.KMnO4 cannot be
used with cotton balls/ribbons. It is only possible with hypochlorite. Black sulfur is not process able with
hypochlorite as sulfur reacts vigorously with sulfur and pace of process cannot be controlled
Procedure:
In this process we take bleaching agent in washing machine then we put small pieces of towel or
cotton (raw cotton) then we will run the machine for few minutes until the towel soaked the bleaching
agent. Then we drain the bleach after that we put the garments in the machine with towel pieces and run
the machine until we get a required effect. We immediately neutralize the garment to prevent bleach spots
or patches.

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7.4 Enzyme wash:
It is environmentally friendly wash. It involves the Application of organic enzymes that eat away
at the fabric, i.e. the cellulose. When the desired color is achieved, the enzymes can be stopped by changing
the alkalinity of the bath or its temperature. Post treatment includes final rinsing and softening cycle. The
effects produced by the cellulose enzyme are---1. Use of cellulose making the seams, hems,
and pockets more noticeable
2. Salt pepper effect is color contrast effect.
3. Faded garment with acid cellulose enzyme provides less color contrast in proportion to garment washed
with neutral cellulose enzymes.
There are four kind of Enzymes available in market for Denim Laundry business.
 Amylase…. Desizing
 Cellulose…. For Salt & pepper effect , contrast
 Lactase…. … bio bleaching
 Catalase…… Peroxide killer

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Enzyme is kind of protein that is obtained from fermentations method from naturally existing
bacteria & fungi. The structure of Enzyme is a biological polymer and it can be found in every cell.
Generally called as Cellulose & it works on cotton (Cellulosic fiber) only. Enzyme are living organisms
which will attack a specific molecular group. There are mainly three kind of Cellulose being used for
Denim washing, Neutral, Acid and Bio polishing Enzyme.
Enzyme are very sensitive with parameters in washing cyclize, pH, Temperature & time. If any of
these parameters are not up to the mark, result will not be accurate. The reaction of enzyme can be easily
controlled, its biodegradable products, so they ecofriendly. Bio Polishing Cellulose are
being used to have protruded fiber removal from denim & oven fabric. This is also widely known as Anti
pilling enzyme. Any Cellulose used in process must be cleaned/killed after the process completion by
simply disturbing the parameters i.e. by raising high temp. Or raising pH to alkaline where no Cellulose
withstand. Cellulose are available in 3 categories
1. Neutral
2. Acidic
3. Hybridenzymes.
Neutral enzyme gives better salt & pepper effect with very less back staining & itsgenerally come
sin powder form & also retains better strength of fabric than acidic Cellulose. Whereas acidic cellulose
give faster results but with too heavy back staining &cuts down the indigo color, also affects the strength
of fabrics. Now a days
laundry people needs faster results in less time & money hence chemical suppliers combined Neutral& a
cid cellulose in such way that it works faster & with better results than acid cellulose with cost
effectiveness & known as Hybrid enzyme. Lactase is bio bleaching agent & alternative for conventional
bleaching agents. This impart greyer cast to blue denim & enhance salt& pepper effect. But due to high
cost & low self-life, laundries do not prefer it.

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Clean up:
After finishing Enzyme wash it is must to add cleanup process for better results &garments appearance &
that can be done in various ways & methods. As cleanup is must process to be carried out after every
chemicals steps done for any garments which allows next process to happen smoothly. All processes
mentioned below kill/ deactivate the active enzymes process. Which is necessary in order to protect/retain
garment strength.
 HydrogenperoxideinalkalinePhclean up enhances the brightness & rich bluestone of indigo.
 By using nonionicdetergentsin medium to high temperature
 By doing two good hotwaterrinseetc.
Process cycle:
7.4.1 Acid wash:
This is the oldest of fashion washes in denim after stone wash. The name acid wash is in reference
to the acids used for this wash in old recipes. In new methods it is done with oxidation. Use of
bleach/oxidative is very safe and economical in comparison to acids. Different chemicals are used and

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Among them potassium permanganate (KMnO4) and sodium hypochlorite are mainly used. Acid
wash is typically done by soaking pumice stone in hypochlorite. Sometime KMnO4 is used in replace of
bleach. Selection of oxidant is very important and mainly depends on the type of fabric. When it is done
with pumice stone the washer and garment should not contain any water. Dry garment is much suitable
for this process then a damp one. Pumice stones are soaked in bleach and left it to open for little time so
they get only damp rather than wet. Then they are processed in machine with garments. The extent of
effect is controlled with process time, concentration of oxidant solution and quantitative ratio of garment
to stone.
Process cycle:
Limitation of acid wash:
 Acid washed, indigo dyed denim has a tendency to yellow after wet processing.
 The major cause is residual manganese due to incomplete neutralization, washing or rinsing.
Other dye:
 Dyeing over the fabric or jeans to add another tone of color
 Most often used is a 'yellowy' over dye to create a 'dirty' look

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 Also can be applied with spray gun or paintbrush for local coloring there are many variations. Blue
and black can be over dyed with bright contrasting colors to obtain special effects. The most
 current and successful forms of overdyeing consist of dyeing washed out indigo jeans with
luminous colors. In this process direct dye is applied into already Indigo dyed garment. It takes 10
pieces of garment and put into the washing machine and add direct dye with all its auxiliaries and
run it for 15mins and check the shade then rinse.
7.4.2Tinting:
Tinting is a process where very less amount of tint is involved & mainly direct dye
is being used to do this process. This is being done to change hue/cast/tone of indigo. Assoon as quantity
of tint color increases & it cover up indigo, reaches the level of dyeing. Tinting being used to give garments
a used / vintage & muddy look. This process takes from 5minutesto15minutes
Time for better results followed by dye fixing & cleans up of superficial dye.
 The garment has been lightly colored in order to give the final denim appearance
 The techniques involve the addition of the colorant in the stone washing cycle.

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 Because of this it must be insured that dyes and cellulose are compatible.
Pigment and local tint (staining):
Need to choose right color of pigment or tint with binder or fixer to apply locally ondenim to get
vintage look. This process also needs an artist to execute it nicely to merge the tint with ground indigo
color & should not look too artificial. Pigments & Local tint also can be applied through spray gun or
rubbing on desired area of denim garment. After application its must be cured in order to have permanent
effect on jean.

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CHAPTER-8
 MECHANICAL WASHES:
1. Stone wash
2. Bio stone washing
3. Sand Blasting
8.1 Stone wash:
Stone washing is a textiles manufacturing process typically utilized by the fashion industry, in
order to give a newly-assembled cloth garments a worn-out appearance. Stone-washing also helps to
increase the softness and flexibility of otherwise stiff and rigid fabrics such as canvas and denim. In the
process of stone washing, freshly
dyed jeans are loaded into large washing machines and tumbled with pumice stones toachieve a soft hand
and desirable look. Variations in composition, hardness, size shape and porosity make these stones
multifunctional. The process is quite expensive and requires high capital investment. Pumice stones give
the additional effect of a faded or worn look as it abrades the surface of the jeans like sandpaper, removing
some dye particles from the surfaces of the yarn.

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Process cycle
Selection of stone:
First pea gravel, then pumice, because they float around with the jeans, instead of lying in the
bottom of the water; Turkish stones are preferred for their porosity and cleanliness or stones from
Sicily, but their supply is limited. Stone should be selected of the proper hardness, shape, andsize for the
particular end product. It should be noted that large, hard stones last longer and may be suited for heavy
weight fabrics only. Smaller, softer stones would be used for light weight fabrics and more delicate items.
Stone wt. /fabric wt. = 0.5 to 3 /1It depends on the degree of abrasion needed to achieve the desired result.
Stones can be reused until they completely disintegrate or washed down the drain.

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Problem caused by stone:
 For instance stones could cause wear and tear of the fabric.
 Damage to wash machineries and garment due to stone to machine and machine to stone
abrasion
 Increase in labor to remove dust from finished garments.
 Water pollution during disposal of used liquor.
 Back staining and re deposition.
 Denim is required to be washed several times in order to completely get rid of the stones.
 The process of stonewashing also harms the big expensive laundry machines.
Black staining and re-deposition:
The dye removed from denim material after the treatment with cellulose or by conventional
washing process may cause "back staining or "redeposit ion. Re-coloration of blue threads and blue
coloration of white threads, resulting in less contrast between blue and white threads.

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Remedy of black staining:
 Adding dispersion/suspension agent to wash cycle.
 Intermediate replacement of wash liquor.
 Using alkaline detergent like sodium per borate with optical brightener as after wash.
Limitation of stone washing:
 Quality of the abrasion process is difficult to control Outcome of a load of jeans is never
uniform, little percentage always getting ruined by too much abrasion.
 The process is non-selective.
 Metal buttons and rivets on the jeans in the washing machines get abraded.
 This reduces quality of the products and life of equipment, and increases production costs.
 Stones may turn into powder during the process of making the garment grayish in color and
rough too
 Provides rougher feel than enzyme wash
 Stone may lead the harm to the machine parts.
Tie and wash method:
Tie & Wash also known as crunch wash or creaking pattern effect is very typical in high fashion articles.
The process is very simple but results to marvelous looks. Garment is usually tied with white cotton strips
and washed with stones. The exposed portions got faded effects and a pattern of dark to light patches
appears on garment. Different patterns can be formed by tying garment in different ways. More beauty is
added when the edges made by tying get prominent in form of white lines made by mechanical rubbing
offered by washer.

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Procedure:
First we do the dry process of garment according to buyer requirement then we fold or bind the
garment and put it into the socks or net and tie it then we put it into the washing machine with
enzyme, stone, back strainer because in this process we get back staining problem b/c it
take a very long time. And we run the machine until we get our require defect. Then we drain it we open
the socks or net and again run the garment with stone enzyme and back strainer to get an even effect
(grains) in the garment.
Net wash:
Another method used for this effect is when net pockets/bags are used instead of tying. The whole
garment is packed tightly in net bag. It should not be fold in proper but a random like filling of one garment
to one bag will give appropriate effects. Then it is stone washed in washer for a time ranges from 20 min
to 80 min depending on the fabric and pattern required.

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Procedure:
First we do the dry process of garment according to buyer requirement then we fold or bind the
garment and put it into the socks or net and tie it. Then we put it into the washing machine with
enzyme, stone, back strainer because in this process we get back staining problem b/c it
take a very long time. And we run the machine until we get our required effect. Then we drain it. We open
the socks or net and again run the garment with stone enzyme and back strainer to get an even effect
(grains) in the garment.
General recipe steps
 Desizing (Tied Garment)
 Stoning or/and Enzyming (Tied Garment)
 Soap Rinsing (Lose Garment)
 Bleaching (if required)
 Neutralization (if required)
 Softener Application
Bio stone washing:
Many garments are subjected to a wash treatment to give them a slightly worn look; example is
the stonewashing of denim jeans. In the traditional stonewashing process,
the blue denim was faded by the abrasive action of pumice stones on the garment surface. Nowadays, de
nim finishers are using a special cellulase. Cellulase works by looseningthe indigo dye on the denim in a
process known as 'Bio-Stonewashing'. A small dose of enzyme can replace several kilograms of pumice
stones. The use of less pumice stones results in less damage to garment, machine and less pumice dust in
the laundry environment. Bio Stonewashing has opened up new possibilities in denim finishing by
increasing the variety of finishes available. For example, it is now possible to fade denim to a greater
degree without running the risk of damaging the garment. Productivity canals be increased because
laundry machines contain fewer stones or no stones and more garments. Below are some celluloses for
denim finishing, each with its own special properties? These can be used either alone or in combination
with pumice stones in order to obtain a specific look.

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CHAPTER-09
 SOFTNEING PROCESS:
Softening process of Denim is very critical. As denim is very heavy in compare with other fabrics
hence its needs softening. During this process there is a big problem -the discoloration of denim i.e. change
in shade or loss of whiteness, giving a yellow tint is commonly known as yellowing. By using normal
softener will lead to ozone problem. Indigo dyed fabric are even more prone to yellowing. As it’s a
widespread problem & There is no single reason for its cause. Instead a number of condition can singly
or in combination lead to the problem. Yellowing in not specific to certain fibers, finishes or washing
processes. It is not specific to chemicals or chemical treatment but certainly some of the factors among
these can lead to the yellowing. As cotton & all
organic polymers develop yellowing in time. Light, acids, impurities, detergents & chemical contribute to
yellowing problems.
Temperature of drying & curing can impart yellowing due to scorching of the cotton. Therefore good
control must be used to minimize this type of damage. Hence it’s advisable to use Anti ozone softener
which prolong ozone reaction of Indigo & keep garment in good condition.
Minimization of yellowing risk:
It’s Impossible to eliminate yellowing but it is possible to prolong & reduce the conditions which
causes classical yellowing.
 Ensure bleaching neutralization & rinsing is proper
 Minimize back staining
 Avoid use of chemicals which cause yellowing
 Avoid leaving garment in open air for longer time
 Control drying & curing temperatures
 Using right Anti ozone softener with right pH

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9.1 Chemical of denim:
1. Bleach fast Indigo
 Value addition to denim
 Retains indigo on certain parts
 Kind of resist effect
 Chemical applied by brush, cured at 150C
 Ex. Indigo fix AXN
2. Anti-depositing agent
 Prevents back staining of fabric by loose indigo during washing
 Improved contrast in denim
 Use in stone step
3. Dye stuffs with softener
 To carry dyeing and softening in one step
 Soft and supple hand
 Saves time, money and energy as added to final rinse
 Gives used and worn out effect
4. Anti-creasing agent
 Provides fabric to fabric lubrication
 Prevents formation of crack marks and streaks
 Minimizes abrasion and gives strength
5. Wrinkle formation
 Creating smooth and permanent wrinkle
 Cross linking concept Ex. DMDHEU
 White pigment
 Can be applied by brush, spray or screen
 Then cured at 150C
 Washed and treated with softener
6. White pigment
 Can be applied by brush, spray or screen

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 Then cured at 150C
 Washed and treated with softener
Process recipe sheet:
9.2 Machine use for denim washing:
Tonellow machine:
Machines suitable for all types of washing processes, such us stone washing, bleaching and other
washing treatments on garments of different materials (cotton, linen, viscose, tinsel treatment etc.).
Particularly indicated for the treatment of jeans, they are supplied with baskets provided with special

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beaters, speeding up the process and guaranteeing at the same time uniformity in the treatment and softness
to the denim fabric. They have variable speed and are equipped with an industrial B&R PC and a PLC
Mod. PP 200. The Software, and in particular the “Wash Program”, entirely worked out by Toneless
Engineers, allows to manage and to control all the functions of the machine as well as the process
operations. It is possible to store up to 500 recipes (with 200 steps/each).
G1 420 LS EVI
Made in Italy
Patented

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TechnicalData G1 420 LS EV1
Cylinder Volume 4180 l
Cylinder Dimensions Ø1890x1490 mm
Variable Speed 0/110 rpm
Installed Power 17 kW
Dimensions
Height 2600 mm
Width 2940 mm
Depth 3100 mm
Weight 4400 kg

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CHAPTER-10
 VALUE ADDITION:
Globally, Denim designers are experimenting with fabric and garment details including
embellishments in order to add value to its garments. New add-ons are being incorporated in the form of
patches, appliqué, rhinestones and glitter. The process of adding value to this legendary outfitter enhanced
from time and time by devising some new methods such as:
Denim washing
A value addition process

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10.1 Overview; Global Textile and Clothing Industry:
In Japan 5.3% upturn in export demand in 2007 as a result of Higher sales to the USA, the EU,
South Korea and Vietnam (13 Mn USD). As for imports, 83.9% of the Japanese clothing import. Market
in 2007 was supplied by China (7.8 bn USD) alone. “China increased its textile and clothing sales to the
USA by 14.8% in volume and 19.4% in value (7.8 bn USD). Despite quota restrictions on a range of
Products.” “Mexico continued to struggle as US importers Shifted orders to China and other low cost
Asian Countries.” “EU output stabilized in 2007, despite a drop in Exports and an increase in imports.
EU imports from China rose by 14.3% to Euro27.5 bn.” Export of knit and woven garment to the US in
million US$

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Global denim consumption Pattern
“About 50% of global denim capacity is now concentrated in Asian mills, and the bulk of this is in
china.”
10.2 Value addition by different process:
Washing: The process
Conventional washing i.e. washing and cleaning
Imparting artistic and innovative look to the garments

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11. FINDINGS:
 To develop softness in garments: Size materials applied during manufacturing that are present in
the fabric are removed, which enhances the soft hand feel. Additional softness may be attained
by using softness.
 To introduce a fading effect: Dyes or pigments present in the fabric, used during coloration, are
washed our locally or partially, resulting in fading or worn- out effects in the garments.
 To create new fashion: The washing process of garments creates a different outlook (faded, color
tinted, etc.), thus creating new fashions for new generations especially for teenagers.
 Removal of starch or size materials gives the fabric a soft hand feel.
 During washing shrinkage may take place; therefore no shrinkage occur during washing of
garments.
 If dirt, spots, impurities, gum, etc. have accumulated in the garments during manufacturing, they
can be removed.
 Comparatively lower capital is required to set up a washing plant.
 A smaller amount of property and fewer paid workers are required to run a washing plant.

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12.DISCUSSION & CONCLUSION:
Our aim for making this report is to provide a new finishes and working on the parameters and
processes use in denim washing. In the whole report we have highlighted denim washing processes and
make our main focus on the processes and washes we had done in rugby industries while in this report we
also describe the manufacturing of denim fabric. The demand of denim is increasing day by day. World-
consumption of denim-wears today is equivalent of about 4,500 million meters per year of denim fabrics.
So to meet this huge requirement of denim new finishes techniques is developed which is economic and
ecological and our textile industry follows all those processes.
Companies that “finish” jeans by washing them or distressing them for a worn -in look. Most major
jeans manufacturers use several different laundries that specialize in different finishes. The main
techniques used include simple washing, stonewashing, which uses an abrasive-bristled tonally machine,
sandblasting, laser burning, or applying enzymes to Simulate “cat’s whisker” -wear line, and sandpapering
by hand.
Generally saying people who don’t know about denim washing then after reading this report you
get a sound knowledge about the whole process which are carried out in
denim preparation and its washing. We include approximately all the major finishes and the process which
involve different operations e.g. wet process and dry process these two are the main operation although
there are also other process but they are the sub process.

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13.RECOMMENDATIONS:
 Garments size changes: Size change takes place owing to the shrinkage properties of fabric.
The amount of shrinkage of the fabric determines the size changes of the garments during
washing.
 Size material is partly removed: Unfixed dyes may remain on the surface of the garments
and it is necessary to remove them completely after washing.
 By using normal softener we lead to ozone problem.
 Indigo dyed fabric are even more prone to yellowing. Light, Acids, Impurities, Detergents,
and chemical contribute to yellowing problems.
Minimization:
 Ensure bleaching neutralization and rinsing each proper
 Minimize back staining
 Avoid use of chemicals which cause yellowing
 Avoid leaving garment in open air for longer time
 Control drying and curing temperature using right antiozonate softener with right pH
REFERENCES:
[1] Denim: Manufacturer, Finishing and Applications. Edited by Roshan Paul
[2] Sustainability in Denim. Editors: Subramanian Muthu
[3] www.slideshare.com
[4] www.textilelearner.com

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