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Internship Report
On
Dyeing, Printing and Quality Control
Submitted To :
Ms. Mandakini Awasarmol
HR Manager
Morarjee Textiles Pvt. Ltd.
Submitted By:
Anand Singh & Dazy Rani
NATIONAL INSTITUTE OF FASHION TECHNOLOGY
HYDERABAD
1
Acknowledgement
This report marks the completion of the two week industrial training program
undertaken as a part of B.F.Tech curriculum.
We are highly thankful to Ms. Mandakini Awasarmol, HR Manager at Morarjee textiles
Pvt. Ltd. firstly for permitting us to undertake this training at such an esteemed
organization and modern processing unit and overall for the facilities that were made
available for us in all the possible ways during this period.
We are also thankful to the head of all the departments for guiding us during the
training period.
We are also indebted to all the staff members and the workers of the Morarjee textiles
Pvt. Ltd for their help and support who helped in making this project possible.
2
Contents1.Introduction..............................................................................................................................6
1.1 History...............................................................................................................................6
1.2 Corporate Profile...............................................................................................................6
1.3 Manufacturing Facilities - Fabric.......................................................................................7
1.4 Departments......................................................................................................................7
1.4.1.Unit II details...............................................................................................................7
1.4.2.Plant Layout of Morarjee Textiles Ltd.........................................................................8
2 . Departments Studied:............................................................................................................9
3. Design Studio..........................................................................................................................9
4. Pretreatment Processing......................................................................................................13
4.1. PROCESSING UNIT......................................................................................................14
4.2. Mercerization..................................................................................................................14
4.2.1. Process Flow: -........................................................................................................15
4.3. Scouring.........................................................................................................................16
4.4. Bleaching........................................................................................................................16
4.4.1. Recipe for bleaching bath........................................................................................17
4.4.2. Precautions..............................................................................................................17
5. Dyeing...................................................................................................................................18
5.1. Dyeing Methods and Procedure.....................................................................................20
3
5.2. Developing solutions......................................................................................................20
5.3. Cold pad batch...............................................................................................................21
5.3.1. Batching time...........................................................................................................22
5.3.2. Problems..................................................................................................................22
5.4. Types of dyeing..............................................................................................................22
5.5. After treatment................................................................................................................22
5.5.1. Recipes and conditions............................................................................................23
5.6. Stenter............................................................................................................................24
5.7. Sanforising.....................................................................................................................25
6. Printing..................................................................................................................................25
6.1. Printing Department objectives......................................................................................27
6.2. Pigments........................................................................................................................28
6.3. Direct Printing.................................................................................................................28
6.4. Discharge Printing..........................................................................................................29
6.5. Screen Printing...............................................................................................................29
6.6. Color Preparation ingredients.........................................................................................29
6.7. Process flow for Reactive Printing..................................................................................30
6.7.1. Ingredients for reactive color Printing......................................................................30
6.8. Process flow for Pigment Printing...................................................................................31
6.8.1. Pigment paste preparation.......................................................................................32
6.9. Process flow of Pigment Discharging Printing................................................................32
4
6.9.1. Ingredients of Pigment Discharge Printing Paste........................................................33
6.10. List of machine, equipments and their specifications...................................................34
6.11. Texfab Loop Ager.........................................................................................................35
6.12. After treatment..............................................................................................................35
6.13. Specifications used in pigment printing and color fixation............................................36
6.14. Texfab Soaper..............................................................................................................36
6.15. Texfab Soaper specifications and activities..................................................................37
6.16. Control parameters and precautions before Printing....................................................37
6.17. Control parameter for Rotary Printing...........................................................................37
6.18. Environmental aspects and impacts of printing............................................................38
7. Quality assurance.................................................................................................................38
7.1. Physical testing..............................................................................................................39
7.1.1. Instruments and tests..............................................................................................39
7.1.2. NORMS...................................................................................................................39
7.1.3. Check points............................................................................................................40
7.1.4. Seam slippage testing.................................................................................................41
7.2. Chemical testing.............................................................................................................42
7.2.1. Description of some test..........................................................................................43
7.2.2. Calculations.............................................................................................................44
7.2.3. Specifications...........................................................................................................44
Conclusion................................................................................................................................45
5
1. Introduction
Morarjee is a name synonymous with fashion. With over a hundred years of experience and
modern integrated manufacturing facilities, Morarjee makes cutting edge fashion a reality. It
has technical collaboration with Swiss and Japanese companies that sets it’s apart in the
industry.Morarjee is part of the Ashok Piramal Group, a diversified and leading business group
in India.
1.1 History
The Morarjee Gokaldas Spinning & Weaving Co. Ltd. is the oldest textile company in India,
established as early as 1871. It is among the first five companies to be listed on the Indian
stock exchanges. In 1935, the mill was acquired by Piramal Chaturbhuj, heralding a new era of
growth and prosperity. Since inception, quality and service were the hallmark of the company.
Riding on these factors, the company has survived the ups and downs in the textile sector.
In the early 90’s the biggest challenge came from World War I. Not only did the mill survive, it
came out much stronger. In 1940, the mill joined the Swadeshi movement and set up a Khaki
department. It won special acclaim from Mahatma Gandhi for this. In 1942 – the Viceroy
awarded a gold medal to the company for the khaki drill.
The 1950’s was the period of unparalleled growth and expansion. The dye house was
modernized with the installation of a continuous open width boiling & bleaching plant, a
modern impregnating unit & a steaming J. Box. This was to improve the fastness of mineral
khaki for which Morarjee Mills have been known for. Next on the cards was acquisition.
Morarjee took over the Sayaji Mills located in Mumbai in 1981 and transformed it from an
obsolete loss making unit to a highly profitable modern textile mill.
Continuous up -of technology and research and development of products has transformed
Morarjee into a leading player in the fabric business. Most of the leading global and domestic
players are its clients today
1.2 Corporate Profile
Morarjee is a leading player in premium cotton shirting fabric and high fashion printed fabric
globally. Morarjee subsidiary company, Integra Apparels and Textiles Ltd specializes in woven
tops, casual shirts and garments for women.
6
Morarjee has a 49% stake in Just Textiles Ltd. which is currently engaged in processing
various fabrics installed at its factory in Ambernath, Mumbai. Morarjee counts most of the
popular international and domestic brands as it clients, across 20 coutries. Dunhill, Zara,
Esprit, Hugo Boss, Next, Paul Smith and Zodiac are some of its customers. In the domestic
market, Morarjee caters to popular brands like Louis Philippe, Van Huesen and Zodiac.
1.3 Manufacturing Facilities - Fabric
Morarjee has an integrated manufacturing plant at Nagpur in Central India. The plant is
equipped to produce premium shirting and high fashion printed fabric for clients across the
globe. To cater to the changing demand and requirements of the fashion industry, Morarjee
believes in investing in product development and technology up-gradation.In the last decades,
two new fabric manufacturing units have been set up in Nagpur. These are supported by state-
of-the-art Design Studios, to keep abreast of the trends in the industry. The company today is
focusing on premium and high value niche product segment and has two divisions - Yarn dyed
shirting division and Printing Division for voile, satin, poplin and other high-end products.
1.4 . Departments
1.4.1.Unit II details
Plant is having following departments: -
1 Spinning 5.Dyeing
2 Weaving 6.Printing
3 Quality assurance laboratory (wet and dry) 7.Finishing
4 P.T.R. (pretreatment) 8.Folding
7
1.4.2.Plant Layout of Morarjee Textiles Ltd.
New process house
Engraving Exit Office
Colour
Kitchen Printing Dyeing Exit
Chemical finishing bleachingstore Folding
Blow Room Weaving Post
Spinning
Spinning Singeing preparatory processes For Weaving
Exit Entry Exit
8
Admin.
2 . Departments Studied:
1. Design studio
strike off
Exposing
2. Processing
Pretreatment
Dyeing
3. Printing
Rotary Printing
Flatbed printing
Gum & Printing Paste Preparation
4. Quality control
3. Design Studio
Morarjee has always played a great role in the fashion movement, for over a century. To
spearhead this, It has set up a state-of-the-art design studio in Italy and India. These studios
are run by creative a team that provide speedy solutions and ideas, customizes designs and
also gives access to the latest international styles, exclusive colors, patterns and designs.
There are 16 members in the design studios. The processes in design studio is divided into
following sections
1. Creation-The design is created and designed according to the specifications given by the
customer. The people from marketing department visit the place and understand about the
design that needs to be printed according to the specifications provided by the buyer.
The design to be printed is decided by :
9
specifications given by the buyer
Trend forecasting
Fashion forecasting
Magazines report
2. Separation: The colors present in the specific design are made in several specific channels.
The color components present in the design are segregated individually to understand the
color requirement according to that design. It is decided by the printing department, design
studio , PPC ,marketing and quality control. The process of separation is done on the basis of
availability of machines & the design specifications given by the buyer. The finalized design is
then sent for engraving or exposing
3. Engraving or exposing: This is the process of engraving the specified design on the
screens so that it can be used for printing processes.
Process flow of exposing:
Unpacking the screen
Changing the curvature of screen that is flat to cylindrical
Degreasing
Coating
Exposing
Developing
Endring
Preparation of Dichromate Solution
100 ml of distilled water + 20 gm ammonium bicarbonate powder
20 % aqueous solution for mixing in photo emulsion
10
Photo emulsion
1 kg photo emulsion + 150 gm distilled water + 50-65 gm ready aqueous solution
The chemical is prepared and filtered, then kept in a freezer for 4 hours before coating.
In mixing, the sensitizer with emulsion make bubbles, so to avoid bubbles it is kept in a
freezer. If we use the chemical directly with bubbles, it will burst during coating and
there will be uneven coating. In freezer the chemical become viscous.
Coating parameter
I. Temperature required - 29-32 0C
II. Drying of screen for 40 – 60 min (rotary screen printing)
III. Nickel screen is used and mesh size of 40-holes/linear inch.
IV. The coating is done in the absence of white light.
V .Light exposure - 35 sec (flat bed screens)
Screens
The screen is made up of nickel alloy, which is minutely perforated in nature, which is used for
printing. The screen comes in three sizes 61cm, 81.4cm, and 91.4cm circumference. Stipper
Acid is used to clean the screens. The cost of one screen for rotary print is Rs. 4,000.and 500
– 1000 m clothes pieces can be printed using one screen. The length of the screens comes in
641.2 mm and 1750 mm. The cost of one screen for flat bed printing machine is Rs. 300 and
once used it cannot be used again for further printing. The screen size is 82” X 42”.and the
design printing area is 60”.Total time taken for screen preparation for flat bed screen Printing is
12 minutes.
Degreaser
When nickel screen is unpacked, it is smooth in nature. It is put in a degreaser to make the
screen rough so that chemical can easily impregnate into the screen and the imprint of colors
on the fabric make denser. The oils, waxes & impurities are also removed and then dry
naturally.11
Endring
In Endring, rings are attached in the ends of the screen so that it can be fitted in printing
machine. ALALDITE Epoxy Gum + Hardener -------- Gum Paste
Gum Paste is applied in the ends of the screen where ring is attached by heating rods at
750W.
Color scanner Technology (CST): In CST, designs are programmed in CAD and black ink jet
draws that design on the rotary screen. The U.V. light passes through the whole rotary screen.
The U.V. light will pass only through the spaces where black ink jet does not draw the design
i.e. the spaces will be blocked by the U.V. light and design remain perforated.
4. Strike Off
The order or design specifications are given by the buyer to the marketing department
and the design studio.
It deals mainly with the sampling of the specified design.
Samples are made on baby rotary printing machine ( screen -9 “X 9” )
Ingredients used for printing is sodium alginate ,urea (10-15 %) ,sodium
bicarbonate ,Turkey Red oil (TRO ) and water (80 % ).
10 -15 made samples are sent to the buyer for approval out of which5-7 samples are
selected for bulk printing.
This process takes a time span of 10 days for the completion of whole process.
BABY STRIKE OFF or BABY ROTARY MACHINE
Type of screen used –Rotary screen
Length of the rod-15Mm
Pressure required-80kg/cm2
Speed-60 rpm
12
Process Flow for Baby strike off
4. Pretreatment Processing
PROCESSING
94.1. PROCESSING UNIT
Department No. Machines
Processing Department 8 BENNINGER JIGGER (capacity-150 kg)
13
Sample Taken Out Ageing Hot Wash with Soap (2gpl)
At 950C (2 times)
Cold WashDryingHalf Piece FinishColour Approval
SINGEING
DESIZING
SCOURING &
BLEACHING
MERCERISATION
2
3
1
2
2
2
3
1
KLEINEWEFERS Mercerization (capacity-2500m)
STAR-HISAKA jet dyeing
ROPE OPENER
SHAKTI JUMBO JIGGER (capacity-250 kg)
YAMUNA JIGGER (capacity- 350 kg)
KUSTER PADDING( cold pad batch)
KIER scouring & bleaching (capacity-2100kg)
PRIMATEX stenter
4.2. Mercerization
Called after its inventor John Mercer. The cloth is
soaked in strong caustic soda and washed under
tension.
The treatment is usually carried out under tension, with caustic soda at 28°- 30° (approx. 270-
330 g/l). This process is important for cotton fabric which is treated with a caustic solution for
improving properties such as fiber strength, shrinkage resistance, luster, and dye affinity.
The yarn or fiber is dipped in a solution of sodium hydroxide and then treated with water or
acid to neutralize the sodium hydroxide. A variation of this process is hot mercerization. It adds
more value to the fabric. This process involves saturation of fabric in caustic soda solution at
higher temperatures and then cooling, stretching and final washing.
Hot mercerization is done.
Cold mercerization faces the problem of non-uniformity due to highly viscous solution.
Concentration of caustic soda is around 280-300 g/l.
Treatment temperature is 50 0C.
Mangle pressure-3.5bar.
10% shrinkage during mercerization.
14
160-165m fabric with width of 2m inside the machine at a time.
A total of 12 rollers are there in bleaching machine.
4.2.1. Process Flow: -
4.3. Scouring
The aim of alkali scouring is to produce an absorbent material with an average degree of
whiteness and extremely low mechanical and chemical damage.
Scouring should be :
– Saponify fats and waxes.
– Split proteins and pectins.
For this, the following are required:
15
WETTING WITH
WATER
PADDING (50 0C,
caustic)
SQEEZING IN
THREE CHAMBERS
WASHING (950C,
20-30 Sec)
NEUTRALIZATION DRYING
CRP (CAUSTIC
RECOVERY PLANT)
Up to 25é NaOH (20–80g/l) and Temperature 1000
4.4. Bleaching
It is the process of decolorization for removing all natural colors from the gray good. It is a
chemical based process. Bleaching
is further classified into oxidative
bleaching and reductive bleaching.
Natural fibers are all generally
bleached with oxidative methods
using such chemicals as sodium
hypochlorite, sodium chlorite or
hydrogen peroxide. In addition to
bleaching, Optical Brightening
Agents (OBA) are also applied to
give the textile material a brilliant
white look.
Oxidative bleaching with peroxide is done
It is combined scouring and bleaching process
Peroxide bleaching is used instead of Hypochlorite because it provides permanent
whiteness and also does not require any antichlor treatment
7 washing zones.
Initially three washers 90 0C, 90 0C, and 60 0C respectively
Last four washers at 90 0C, 90 0C, 90 0C, and 60 0C respectively
Last chamber is meant for neutralization with acetic acid
Running speed of take up roller 40 rpm
It varies with required finish of the fabric16
It has a chain (conveyor belt) system in steaming chamber. Fabric rests over the belt is
plated form and so provides residence time of 13 min.
Soda and Megawet RW is used as commercial reagents in Morarjee textiles.
Fabric has to be tested for
I. PH: - phenolphthalein (colorless to violet) at PH 8-9
II. Whiteness index (spectrophotometer)
4.4.1. Recipe for bleaching bath
Chemicals Quantity (ml/kg)
Peroxide (Megawet RW) 30
Wetting agent 4.5
Stabilizer 24
NaOH 18
Steaming temperature 92 0C
4.4.2. Precautions
Steam flow should be uniform
Sufficient residence time
Uniform pressure.
4.4.3. Problems
Patches may appear sometimes due to improper temperature control in steamer and so roof
temperature is kept slightly higher than base temperature.
5. Dyeing
Often applied to the finished cloth to give a uniform all-over colour. But some weaving is
carried out with yarns that have already been dyed. And printing can also be considered as a
17
dyeing process. The first artificial dye, mauve aniline derived from coal tar, was discovered by
William Henry Perkins in 1856. With artificial dyes there was a much greater range of bright
colours and dyes were developed which were 'fast' and also fade-resistant.
18
DYEING
Jumbo &
Yamuna Jigger
CPB
(Kuster Dyeing)
Small Jigger
19
AFTER TREATMENT
(SOAPER WASH)
FINISHING
STENTER, SANFORISING
WASH
BATCH
5.1. Dyeing Methods and Procedure
Dyeing Methods Procedure
CPB Dyeing(1000ml) Color + 60 ml water + 20ml urea
10 ml soda (for light shades)
20 ml soda + Caustic (20 :5) (for medium shades)
20 ml soda + Caustic(20:8) (for dark shades)
Batching Light shade - 8 hrs
Medium shade - 8-12 hrs
Dark shade - 8-14 hrs
Washing Normal - 60 0C
Hot wash - 95 0C
Soaping - 95 0C
Neutralization - Ph 4.5
Washing (cold wash)
5.2. Developing solutions
Reactive dye: - 20 g/l Glauber salt + 20 g/l soda ash + 5 g/l caustic soda + 3 g/l resist salt.
20
Dyestuffs:-
5.3. Cold pad batch: -
Silicate padding is done.
Bath temperature is kept 200C.
Dye liquor containing urea is fed into the tank along with alkali.
Dye liquor: alkali- 4:1.
21
Colour Name Reactobond col.
strength
Jakofix col.
Strength(%)
Reactobond
quantity(gram)
Jakofix
quantity(gram)
Red H8B 100% 126 1000 793
Blue H3RP 100% 113 1000 885
Brown H4R 100% 107 1000 935
Orange H2R 100% 104 1000 961
L.Yellow H4G 100% 136 1000 735
G.Yellow HR 100% 95 1000 1052
Black HN 100% 131 1000 763
Purple H3R 100% 103 1000 970
T.Blue P5G/HN 100% 124 1000 806
Black CECL/XLW 100% 100 1000 1000
Air pressure-7 bar.
Speed-40m/min.
Mangle expression (CPB-2)-60%.
5.3.1. Batching time: -
12-14 hrs for medium and dark shades
8-10 hrs for light shade
Washing is done after batching.
5.3.2. Problems: -
Patches-Adjust the speed to maintain proper residence time.
Stitch marks-Plastic paper is placed over the seam.
5.4. Types of dyeing
Reactive dyeing
DEPTH SALT (g/l) SODA (50 %) CAUSTIC (ml/l)
0-0.5 % 30 10 1
0.5-1.5% 40 12 1
1.5-3 % 60 15 1
3-7 % 80 20 1
Black 100 5 2
5.5. After treatment
SOAPER
Stenter wash at 300C.- 400C without soap and acid.
22
Counter flow washing is done.
18 drying rolls.2 cooling rolls
135m fabric inside the machine at a time
150m inside relax chamber
25000L water in each chamber
Fabric speed-35m/min
Expander rolls at feeding end to remove creases
5.5.1. Recipes and conditions
Pre-softening (on stenter): -
Pursoft 10 g/l
Acetic acid 2 g/l
Washing: -
After construction of fabric through
one of the many techniques described above, it is known as greige good or gray good. This
simply denotes any unfinished fabric. Many finishing processes are employed for improving the
appearance, feel and durability of the fabric. These processes are broadly classified as
Preparatory Processes, Stabilizing Processes, and Textural Processes.
23
Soda 15g/l
Wetting agent 4g/l
Speed 50m/min.
5.6. Stenter
This is basically a smoothing out of the cloth. Because after bleaching, or any wet process, the
cloth will get wrinkled or creased. Stentering (done by "stenterers") removes these bumps.
It is used for: -
I. For OBA application
II. For heat setting
Both pin and clip arrangements are used
Oil heating mechanism for drying
7 chambers in stenter.
Bowing and heading rollers at the feed end to remove creases.
Fabric speed: -50m/min
Speed and temperature are two important parameters
CHAMBER NO LIGHT SHADE MEDIUM SHADE DARK SHADE
1 110 0C 110 0C 110 0C
2 120 0C 120 0C 120 0C
3 130 0C 130 0C 130 0C
4 140 0C 140 0C 140 0C
5 140 0C 140 0C 150 0C
6 140 0C 140 0C 150 0C
7 140 0C 140 0C 150 0C
24
Faults
Pin holes
Yellowing
Oil spots or soiling
5.7. Sanforising
It is pre shrinking finishing
Rubber belt shrinks the fabric along with it
Shrinkage > 5 %
Speed 50 m/min
Steam heated roller over belt at 110 0C
50 m fabric from in to out
After shrinking zone, there is a setting zone to set the shrinkage in fabric
Fabric is cooled and then batched
Some shade variation may occur
Pressure-9kg/cm2
6. Printing
It is the process of transferring the given design on the specified fabric by the printing
department. Printing is a very economical means of producing patterned material. The dye is
applied by rollers and flat bed screens and each color is applied separately
PVA is used for the adhesion of fabric on conveyor belt
Speed 80-90 m/min
Dummy rollers to remove surface impurities
25
Maximum screens are possible
Rangolite is used as discharging agent in paste form
Belt is washed and used again.
Printing department process flow
26
Marketing
DESIGN STUDIO
planning ,separation, engraving, exposing and screen frame checking
Washing
AGEING or CURING
PRINTING DEPARTEMENT
Planning for colors, chemicals and fabric printing
s/off approval and D/P design Cad approval
Quality or Fastness Checking
Delivered to finishing
6.1. Printing Department objectives under ISO 9001 -2008
Sr.no
.
Objective Current level Target level Date Action
1. Reduce cost of
printing dyes and
chemicals
7.0 % 6.84 % March
2012
Modify recipe and
reuse the dyes
2. Increase
packaging
percentage of
printed fabric
93.05 % 93.45 % March
2012
Steps to control
defects
To achieve the
OTIF %
EXPORT
92.05 %
RMG
72.08 %
EXPORT
95 %
RMG
75 %
March
2012
Co-ordination
between PPC,
marketing, QC and
customers
Styles of printing
Direct Style Discharge Style Resist Style
Pigment Discharge
Reactive colour Pigment Colour
27
6.2. Pigments – These are dry particles that give colour to ink. There are various types of pigments such as
organic and inorganic. Organic pigments contain carbon and hydrogen and most are made
from petroleum. Coal, wood, animal fats, and vegetable oils are also used in organic pigment
manufacture. Generally there is a wider selection of colors in relationship to inorganic
pigments. Colors tend to be richer, brighter, and more transparent.
Inorganic pigments are chemical compounds, typically formed by precipitation. Pigment colour
is determined by the proportions of the chemicals used to produce a pigment. Ink made with
inorganic pigments are less expensive to produce than those made with organic pigments.
They give good opacity but lack some of the qualities of organic pigments inks, such as
transparency. Pigments are classed as opaque and transparent pigments.
Opaque pigments are used when transferring an image to cover a substrate or when
overprinting another colour. Opaque whites are also used for mixing with other inks to lighten
the colour or hue. Many times a printer will print opaque white to help "hide" the influence of a
dark colour paper on the overprinting ink. Transparent pigments are used to allow the
background material or ink to be seen. All process colors (black, cyan, magenta and yellow)
are transparent. Process inks need to be transparent to allow the proper tapping mechanism to
occur.
6.3. Direct Printing:-
It is the most common approach to apply a colour pattern on fabric. It can be done on white or
a coloured fabric. If done on coloured fabric, it is known as overprinting. The desired pattern is
produced by imprinting dye on the fabric in a paste form. To prepare the print paste, a
thickening agent is added to a limited amount of water and dye is dissolved in it. Earlier corn
starch was preferred as a thickening agent for cotton printing. Nowadays gums or alginates
derived from seaweed are preferred because they are easier to wash out, do not themselves
absorb any colour and allow better penetration of colour. Most pigment printing is done without
thickeners as the mixing up of resins, solvents and water itself produces thickening.
28
6.4. Discharge PrintingIn this approach, the fabric is dyed in piece and then it is printed with a chemical that destroys
the colour in the designed areas. Sometimes, the base colour is removed and another colour is
printed in its place. The printed fabric is steamed and then thoroughly washed.
6.5. Screen Printing
It is done either with flat or cylindrical screens made of silk threads, nylon, polyester, vinyon or
metal. The printing paste or dye is poured on the screen and forced through its unblocked
areas onto the fabric. Based on the type of the screen used, it is known as 'Flat Screen
Printing' or 'Rotary Screen Printing'.
A significant characteristic of screen printing is that a greater thickness of the color can be
applied to the substrate than is possible with other printing techniques. This allows for some
very interesting effects that are not possible using other printing methods. Because of the
simplicity of the application process, a wider range of inks and dyes are available for use in
screen printing than for use in any other printing process.
Utilization of screen printing presses has begun to increase because production rates have
improved. This has been a result of the development of the automated and rotary screen
printing press, improved dryers, and U.V. curable ink. The major chemicals used include
screen emulsions, inks, and solvents, surfactants, caustics and oxidizers used in screen
reclamation.
6.6. Color Preparation ingredients
Required amount of colour is taken.
TRO is added and dissolved in hot water at 60 0 C.
The above made paste is added to the gum paste i.e. sodium alginate paste.
1. For blotch color-mix for 10-12 min. 2. For motif colour –mix for 5-7 min.
The viscosity of the paste is measured.(blotch 25-30s & motif 45-60 seconds)
The colour paste is filtered using polyester bolting cloth and labeling is done
29
6.7. Process flow for Reactive Printing
6.7.1. Ingredients for reactive color Printing (1000 liter)
Ingredients Amount (in kg)
Hexa phosphate 3kg
sodium alginate 12 kg
CHT alginate 12 kg
Ludigol AR (softening agent ) 4 kg
Urea _
thickening agent Sarex –Al -1 _
sodium Bicarbonate (Alkali ) 35 kg
Mega print PRA (viscosity) 10 kg
30
Printing Drying Ageing
Ready for
finishing
Washing
6.7.2. Reactive color Paste Preparation
1. The vessel is cleaned.
2. Stirrer is started and 3k of sodium Meta hexa phosphate is added and left for 10 min.
stirring.
3. Add 12 kg of sodium alginate and 12 kg of CHT alginate while stirring as a thickening agent.
4. Stirring of gum is done for 4 hours.
5. The gum is cooled down and urea is added to reduce and maintain the temperature of 45
deg. Celsius.
6. 4 kg of Ludigol AR is added to the water for the softening action and added to gum paste.
7. Now the thickening agent Sarex –Al -1 is added in water and added to gum paste.
8. Now 35 kg of sodium Bicarbonate is added for the alkaline medium maintenance and stirred
for 10 min.
9. 10 kg of Mega print PRA is added to gum and stirred for 10 min. and the viscosity of the
paste is checked (60-90 viscosity )and PH is checked (PH =8.5).
10. The gum paste is stored then in large tanks.
6.8. Process flow for Pigment Printing
31
Printing Drying Curing
Quality
checking
Finishing
6.8.1. Pigment paste preparation
Vessel is washed and 70 liters of water is added.
Kept in stirrer and 6 kg of binder FBET and binder FBTW is added and run for 5 min.
Urea is added and run for 5 min.
25 Kg of Luprintol MCL and Luprintol PE New is added to the solution and run for 15
min. and 5 min, respectively.
6-8 kg of Lutexal HEF 97 is added and run for 15 min.
0.5 Kg of Liquid ammonia is added and left for 20-30 min. and stirred.
6.9. Process flow of Pigment Discharging Printing
32
Printing Drying Ageing
CuringWashingQuality
Checking
Finishing
6.9.1. Ingredients of Pigment Discharge Printing Paste
Ingredients Parts
Water 168 parts
Pidicryl Binder BN 15 Parts
Tri –ethanol amine (TEA ) 1 part
***Liquid Ammonia 1 part
Pidimine S1/100 2.5 Parts
Urea 3 Parts
Pidicron DTS 10 Parts
Total = 100 Parts
*** Around 1-2 % of Pidiprint 160 (thickener) is added in the above mixture so that it becomes
slightly thicker and does not come out during stirring.
6.9.2. Pigment discharge paste
Vessel is washed and 70 liters of water is added.
Kept in stirrer and 6 kg of binder FBET and binder FBTW is added and run for 5 min.
Urea is added and run for 5 min.
2.5 Kg of Luprintol MCL and Luprintol PE New is added to the solution and run for 15
min. and 5 min, respectively.
15 kg of Rangolite ST to paste and run for 15 min.
6-8 kg of Lutexal HEF 97 is added and run for 15 min.
0.5 Kg of Liquid ammonia is added and left for 20-30 min. and stirred.
33
6.10. List of machine, equipments and their specifications
Sr.No. Specification Rotary M/C Busher Flat
Bed M/c
Ichinose Flat
Bed M/c
Baby Rotary
M/c
1. Make Stormac T. Maneklal Ichinose M-Tex
2. Model Stormac IV Hydromag III Ichinose 7000
3. Yr. of mfg. 1984 1980 2006 2005
4. No. of colors 13 10 12 2
5. Function Pneumatic Hydraulic Pneumatic Hydraulic
6. Printing width 1850 mm 1575 mm 2100 mm 1850 mm
7. Speed max. 70 mtr/min 7-8 mtr /min 10-18 mtr /min 5 mtr/min
8. Screen used Nickel Metal Polyester
Bolting cloth
Polyester
Bolting cloth
Nickel Metal
9. Printing blade 5 s Rubber Rubber Magnet rod
10. Blanket
length
16.5 mtr 50.8 mtr 61.5 mtr 16.5 mtr
11. Blanket width 2060 mm 2000 mm 2400 mm 2060 mm
12. Printing Warpwise Weftwise Weftwise Warpwise
13. Design
repeat
Fixed 64.2 cm Variable upto
3000 mm
Variable upto
3040 mm
Fix 64.2 mtr
14. No. of dryer
chamber
4 1 1 1
34
6.11. Texfab Loop Ager
50 loops
For 200 meter of fabric ageing can be done in one move.
Curing by oil heating at 150 0C for 3-5 min
Ageing by steaming at 1020 – 103 0 C for 6-8 min.
950 kg / hr steam pressure and the time of contact is 9-10 min. during Ageing.
6.12. After treatment
Specifications of Equipments and Machinery used
Sr. No. Specification Arioli Loop
Ager
Texfab Loop
Ager
Texfab soaper
1. Make Arioli (Italy) Texfab (India ) Texfab (India )
2. Yr of manufacture 2004 2006 2007
3. Machine function Manually Automatic Automatic
4. Roller width 78 “ 101 “ 78 “
5. Working width 72 “ 98 “ 72 “
6. Fabric capacity 200 mtr 230 mtr 180 mtr
7. Used for Developing
reactive and
discharge
colour
Developing
reactive and
discharge
colour
For washing
clothes
8. Production/day 20,000 mtr /day 40,000 mtr /day 35,000 mtr /day
35
6.13. Specifications used in pigment printing and color fixation (ageing stage)
Reactive Printing Pigment
printing
Discharge
printing
Color
fixation
Temperature 110-1400 C 120-1550C 90-1200 C _
Air pressure 4-7 kg/cm2 4-7 kg/cm2 4-7 kg/cm2 _
Squeeze blade 45 x 0.15
45 x 0.20
45 x 0.15
45 x 0.20
45 x 0.15
45 x 0.20
_
Chamber temp. _ _ _ 102-1040 C
Contact time _ _ _ 9-10 min
Loop length _ _ _ 4 mtrs.
6.14. Texfab Soaper
Made from Texfab Company (Surat).
7 tanks for hot washing and cold washing.
16 dryer chambers and 4 cooling chamber.
36
6.15. Texfab Soaper specifications and activities
Tank Capacity Temperature Process carried out
Tank 1 980 ltr _ Cold wash (500 gm Hcl for 600 mtr )
Tank 2 1750 ltr _ Cold wash spray and overflow
Tank 3 1400 ltr 65 0 C Hot wash
Tank 4 1200 ltr 950 C Hot wash with soap (Dekol )
Tank 5 1200 ltr 950 C Hot wash with soap 1.5 gpl
Tank 6 1400 ltr 900 C Only hot wash temp. 950 C
Tank 7 980 ltr _ Only cold wash with spray
6.16. Control parameters and precautions before Printing:
PH of the printing paste should not be less than 9.
After making the color the PH checking becomes difficult so keep some color extra for
PH checking. If the PH is less then add some liquid ammonia to maintain the PH.
Same amount of ammonia should be added to paste as well as color before printing to
avoid the defects, fuzziness and the bubbling in the print paste.
6.17. Control parameter for Rotary Printing :
Proper cleaning of rotary screen is done to avoid regular check up of the screen
while printing is in process.
Setting of pressure of magnetic rod and squeeze blade is done properly to avoid
the misprints and other printing defects.
The tension of the conveyer is adjusted properly so that the spots and stains can
be avoided.
37
6.18. Environmental aspects and impacts of printing :
Aspects Impacts
Use of chemicals Excess chemical consumption
Use of steam Resource depletion
Spill or leakage of chemicals Soil and water pollution
Fumes and heat Human discomfort in summer
Use of oil and grease Spent oil and hazardous wastes
Steps of improvement
To improve the safe working practices Use of PPE (personal productivity
equipments) and make available MSDS
(material safety data sheet )
Conserve water resources Use of recycled water from ETP (effluent
treatment plant )
7. Quality assurance
Quality assurance department works on in process quality control. It maintains the quality
standards.
It has been divided into separate zones, which work independently.
Lab dip section
38
In process control
Finished product inspection
Note: - ISO/AATCC standards are followed.
7.1. Physical testing
7.1.1. Instruments and tests: -
Seam Slippage/Tensile Tester (H5RT)
Tearing Strength Tester (Paramount)
Crock Meter (Paramount)
Washing Fastness Testing
Computerized Twist Tester (BTRA)
Random Tumble Pilling Tester (SDL atlas)
Martindale Pilling Tester (SDL atlas)
Wrap Reel (Kamal metal ind.)
7.1.2. NORMS: -
Tensile strength: - minimum 25 lbf
Tear strength: - minimum 1.5 lbf
Seam slippage: - 15 lbf
Pilling (Martindale) ---- 4
Color fastness
I. Light shade ---- 4
II. Medium shade --- 3 – 4
39
III. Dark shade 3
Rubbing fastness
I. Light shade ----- 4
II. Medium shade ----- 3
III. Dark shade ------ 2 – 3
7.1.3. Check points
WEIGHT/ sq meter and WEIGHT/linear meter
Width of fabric
Fabric construction of woven fabric
BOW: - bow occurs when yarns are displaced from a line perpendicular to the selvedge
and form one or more arcs across the width of the fabric
I. Take a full width specimen and level the weft yarn
II. Then a straight edge is placed across the fabric between two points at which the last
reversed yarn meets the two selvedge or edge
III. Maximum distance or deviation from straight edge is measured
IV. Measure the full width of the test specimen
V. % Bow = (max deviation in cm)*100/full width in cms
Dimensional change
Tearing strength (pendulum method)
Fabric construction (ASTM D 1375) :- no of ends or picks falling per unit distance when
fabric is held without tension
DCAHL (AATCC – 135): - determination of dimensional change in test specimen when
subjected to repeated laundering
40
Seam slippage (ASTM D 434)
Crease recovery angle (AATCC 66)
Abrasion resistance (Martindale ASTM D 4966-98)
Pilling resistance (ASTM D 497-99)
Absorbency (AATCC 79-59)
Whiteness using spectrophotometer
Color fastness to washing
Water fastness (AATCC 107 – 199 D)
Perspiration fastness
7.1.4. Seam slippage testing
Test the suitability of woven fabric seaming.
Seam slippage is the load required to produce a specific amount of opening in a given
direction (warp over weft or weft or warp)
In “warp over weft” warp yarns moves/slides over the weft yarn and vice versa
Cut a piece of fabric 4*14 inch with long direction parallel to the weft yarn for warp yarn
slide over
Fold the specimen 4 inch from one end with the fold parallel to short direction of the
fabric (face to face)
Sew a seam of about ¾ inch from crease of folding 40/3 spun PET thread with 0.03 inch
needle in diameter
Cut the fold open
Fold the entire specimen at equal distance and cut an un-seamed sample
Cut three samples
41
Condition the specimen
Set the machine at 75 mm jaw separation 300m/min speed
Test the seamed and un-seamed sample (seam should be between upper and lower
jaws)
7.2. Chemical testing
This is done to check the purity of chemicals
NORMS: -
CHEMICAL PURITY
Caustic soda > 47 %
H2O2 > 49 %
Sodium hydrosulphite > 84 %
Hypochlorite > 40 g/l of available Cl
Glauber salt 6.5 < Ph <7.5
Alginate Moisture 10 – 15 %
MgCl2 > 95 %
Resist salt > 95 %
Soda ash > 93 %
Hardness < 300 ppm
pH 6.5 – 8.5
42
7.2.1. DESCRIPTION OF SOME TEST
Test Procedure
Concentration of recovery
caustic
I. Take 5 ml sample of caustic and add 500 ml of water.
II. Take 10 ml from this solution and titrate it against 0.1 N HCl using
0.1 N phenolphthalein as indicator.
Gram per liter = B.R.* 40
Testing of H2O2 I. Take 5ml peroxide soln. Add 5ml (20%) sulphuric acid.
II. Titrate against KMNO4 (0.588 N)
End point: colourless to pink
Reading*2= grams/lit
Testing of Caustic soda I. Take 2 ml caustic soln. Add 2-3 drops of indicator
phenolphthalein.
II. Titrate it against 0.245N HCl
Reading * 2= grams/lit
Purity of Caustic soda I. Take 5-6 gm of sample in 500 ml of water
II. Take 25 ml of this diluted solution in conical flask
III. Titrate it against 0.1 N HCl using phenolphthalein and methyl
orange as indicator.
IV. Color change pink to colorless and yellow to orange.
43
7.2.2. Calculations
Test Procedure
mg/l of chlorine in water I. Take 100 ml of water sample and titrate it against 0.02 N
AgNO3
II. Use 4 % K2Cr2O7 as an indicator with end point of yellow
to red.
Chlorine in water (mg/l) = B.R* 10
Testing of NaOCl III. Take 5ml of soda bleach solution. Add acetic acid &
potassium iodide(10%)
IV. Titrate with sodium thiosulphate(0.28 N)
End point:-Brown solution turns colourless
Reading *2=gram/lit
7.2.3. Specifications: -
For mercerized sample: -
Whiteness – minimum 75
Residual size – min 7 (on a scale of 1-9)
pH
I. Full white 5.5 – 7.5
II. Dyed 5.5 – 7
Absorbency
Finished < 10 sec 44
Conclusion
The textile internship has been completed in Morarjee Textiles Ltd, Nagpur, Maharashtra. The
duration of the internship was of two weeks where we had covered designs studio,
pretreatment of cotton fabric, dyeing, printing and quality control & assurance methods of
textile processing. We study the various aspects of a textile processing unit starting from
design section to the functionality of the various departments. We are introduced to the various
brands of machineries available for carrying out the different textile processes to meet global
standards. The internship helps us to understand the structural and functional constituents of
the industry and also adapt to real industrial situations which equips us for decision making in
a realistic environment
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