Textile Printing Process Guide

CHEMICAL PROCESSING
PRINTING
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Objectives
• The main objective in printing is the production of attractive
designs with well defined boundaries made by the artistic
arrangement of a motif or motifs in one or more colours
• Dyes and pigments are applied locally or discontinuously to
produce the various designs
• Localized dyeing
• The forces which operate between dye and fibre are the same
in dyeing and printing
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Ingredients
The essential ingredients of printing paste are selected from
the following:
1. Dyestuffs, pigments or dyestuff formers
2. Wetting agents
3. Solvents, solution aids, dispersing agents and humectants
4. Thickeners
5. Defoaming agents
6. Oxidizing agents and reducing agents
7. Catalysts and oxygen carriers
8. Acid and alkalies
9. Carriers and swelling agents
10. Miscellaneous agents
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Styles of Printing
A coloured design on a white or differently coloured
background can be produced on fabrics by using different
styles of printing like direct style, discharge style and resist
style
Printing Style
Direct Discharge Resist
White Coloured White Coloured
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Discharge style
• Azoic Dyeing
• Print fabric with gum and
Rongalite C (H liberation)
Steam
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Resist Printing
•Dyes that could not be
discharged can be resisted
•Print Citric acid with
thickener ̶ Dry
•Pad with with reactive dye
liquor
•Steam
•Soap
Citric
acid
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After Printing Operations
• Drying
• Fixation
Steaming
Curing
• Washing-off
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Pigment Printing
Pigment printing Printing with dyes
No affinity to fibre. Affinity to fibre.
Insoluble in water. Water soluble or can be made
water soluble
Need binder for fixation onto
fibre
Held on fibre by dye-fibre
interactive forces.
No washing require Washing require
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Print Paste
• Dye--- 5 parts
• Wetting agent- 1 part
• Glycerine- 5 parts
• Thickener paste– 69parts
• Water- 20 parts
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DYEING and PRINTING
•Printing is controlled form of localised dyeing
•Same mechanisms of dye fixation apply in both
dyeing and printing
•In principle dyes used to produce dyed fabric could
be used to print that fabric
•However care is needed in selection of dyes
•In printing dye solubility is more critical
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•The amount of water in the print paste is severely
limited
•And at the fixation stage, the dye must be re-
dissolved in a small volume of condensed steam
•The dye must diffuse through the thickener film
before adsorption on, and diffusion into, the fibre
•Slow diffusing dyes will need longer fixation
(steaming, ?) times
•Low mol. Wt. dyes are preferable (if fastness is not
compromised)
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General procedure for printing
Preparation of Printing paste
Printing
Drying
Fixation (Steaming/dry heat etc.)
After-treatments
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General Nomenclature
• Thickener paste---Only thickener prepared as per solid content
required to build final viscosity
• Stock paste--- Except dye/pigment all ingredients
• Print Paste– Final paste for printing including dye/pigment
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DIRECT PRINT COLORATION of cellulosic fabrics-
1.Direct dyes
• Printing paste generally contains dye, wetting agent, solvent,
hygroscopic agent and weak alkali
• Thickener – preferably starch or british gum (Dextrin)
• Typical recipe for Print Paste (1Kg paste)
Direct dye – 5-20gm
Water – 385-310gm
Glycerine– 50gm
Trisodium phosphate- 10-20gm
Thickener- 500gm
• After printing fabric is dried and steamed for about 1hr in cottage
steamer (batch process) or 5-10mins in continuous steamer followed by
light soaping and the washing
• The washing fastness of the prints may be improved by after treatment
with cationic dye fixing agent
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DIRECT PRINT
COLORATION
REACTIVE DYES
Printing by the all-in method
Stock Paste
Print Paste
Dye—X gm
Water--
Stock paste—
Maintain viscosity---?
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A typical print paste is prepared by sprinkling the required
amount of reactive dye into a stock paste
or
Adding the pre-dissolved dye in a small volume of hot water
• Alginates are the only suitable natural thickeners
• Synthetic thickeners with anionic charges Poly (acrylic acid)
are also good. Washing-off is difficult
• Emulsion thickening can also be used

ALKALI
•Alkali is needed to ionise accessible cellulose
hydroxyl groups and fix the dye
•Depend on reactivity/stability of dye
•Sodium bicarbonate has been the preferred alkali
•It is cheap and gives sufficient print paste stability
with most reactive dyes
•For high stability dyes, sodium carbonate can be
used
•For dyes of high reactivity the concentration of
bicarbonate may be reduced
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FIXATION
• It is important to ensure that the fixation (maximum) and
hydrolysis (Negligible) proceed to completion
• The choice of dyes is therefore determined by the fixation
equipment available
• The stability of the dye–fibre bond under hot alkaline
conditions is important
• Print paste stability and dye reactivity are related
• The actual level of fixation is also important
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• The fixation of most reactive dyes is effected by
saturated steam at 100–103 °C within 10 min.
• The most highly reactive dyes may require only 1 min
• Faster fixation is obtained in superheated steam at
temperatures of 130 -160 °C, 30 to 60 s
• higher fixation levels can be achieved by having two
reactive centres into each dye molecule
FIXATION
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ROLE OF UREA
• Solubilizing aid for reactive dye
• When cold printed fabric is entered into
saturated/superheated steam, water condenses on to
the fibres
• But loss of this water follows
• Urea holds some of the water very strongly
• The eutectic mixture of urea and water provides the
solvent required for the dye–fibre reaction to occur
• In the absence of urea colour yields are low, unless
fixation can take place during drying
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FIXATION IN HOT AIR
•Because reactive dyes are typically of small
molecular size and low affinity, fixation can be
achieved even in hot, dry air.
•Urea at concentrations of 150–200 g/kg of paste is
essential
•Times of 1–3 min are required at temperatures of
180–160 °C.
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PRINTING BY TWO-STAGE METHODS
The composition of a typical
stock paste
Recipe for wet fixationprocesses
Print Paste
Dye—X gm
Water--
Stock paste—
Maintain viscosity---?

• The alkaline solution can be applied on a vertical two-bowl
padder at high speed or, if lower speeds are used, on a
horizontal two-bowl or nip pad.
• The steam temperature is preferably at least 130 °C, for a
steaming time of 30–50 s.
• Washing equipment is usually coupled with the steamer for
immediate removal of unfixed dye.
PRINTING BY TWO-STAGE METHODS
Nip padding
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“ALKALI SHOCK”
• Alkali-shock method to fix the reactive dyes in which printed fabric
goes through into hot alkali solution (100–103°C) to initiate fixation.
• For dyes of high reactivity, steaming is not required
• A passage in open width for 10–20 s through the alkaline liquor at
followed by immediate washing.
• Elevation of the boiling point – bath temperature can go upto 105oC
(which chemical should be added?)
• bleached fabric → printing → alkali-shock → rinsing → soaping →
rinsing → drying.
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• Longer fixation times, lower (room) temperature
• Sodium silicate liquors are used by padding
• Wet pick up is 70–80%
• Fixation takes place slowly ( 6–12 h ) during batching
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•Washing is a critical step (more than that for dyeing)
•A perfectly fine printed fabric can be spoiled at
washing stage
•Selection of dyes is important
•High substantivity dyes – problem in removal during
washing
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•The first step is a thorough rinsing with cold water
•Alkali, electrolyte and most of the thickener and
surface dye (hydrolysed) should be removed in the
first stage
•High-temperature washing (~boil) is then done
remove hydrolysed dye from inside the fibres
•Finally a cold rinse is given
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Direct Print Coloration of Polyester– Disperse
Dyes• Disperse dyes are most suitable
• Thickener is important. It should adhere to fabric and produce elastic film.
• Natural gums, starch ethers and Indalca gum is commonly used. Combination of thickeners
can also be used
1. For high pressure steaming
Disperse dye- 50-100gm
Water- 50-104gm
Thickener paste – 894-790gm
Ammonium sulphate- 5gm
Sodium chlorate/ R-salt– 1gm
• After printing and drying, the fabric may be steamed for 30 min at 25psi pressure (125-
1300C).
• Alternatively hot air fixation may be carried out at 180-2000C for 1min.
• The fabric is then rinsed with hot water and reduction cleared using 2gpl NaOH and 2gpl
hydros
2. For thermal Fixation
Disperse dye- 50-100gm
Water- 50-100gm
Carrier – 0-20gm
Thickener paste- 900-780gm

DISCHARGE &
RESIST
STYLES
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DISCHARGE AND RESIST
STYLES
• Involve two stages as compared to direct
printing, which is a single stage process
• In discharge style, dyeing of the fabric is
followed by printing
• In Resist, it is the other way round
(Printing followed by dyeing)
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DISCHRAGE PRINTS
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Discharge Style of
Printing• In the direct printing style, the final effect is obtained in one operation
• In the discharge style, the fabric must first be dyed with dyes that can be
destroyed by selected discharging agents (white discharge)
• A coloured discharge effect is produced by adding a discharge-resistant
(‘illuminating’) dye to the discharge print paste
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Advantages of Discharge
style
• Printed materials with large areas of ground color can be
produced
• Delicate colors and intricate patterns can be reproduced on
grounds of any depth
• Intricate white patterns lose their crispness if left as unprinted
areas in a direct, blotch print
• Difficult to fit a colored motif into a blotch print by direct style
• Aesthetically superior results give the product a higher value
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SELECTION OF DYES: DISCHARGEABILITY
• Dyes which are suitable for the dischargeable ground usually contain azo groups
that can be split by reduction.
• Even so, there are great differences in dischargeability between individual dyes.
DISCHARGEABILITY SCALE
- 1 TO 5
4-5 Suitable for white discharge
3-4 Suitable for colored discharge
1 - Non dischargeable, suitable as illuminant color
SUBSTITUENT ATR1 AND R2 AREIMPORTANT
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CI DISPERSE ORANGE 5 HAS GOOD
DISCHARGEABILITY
CI BASIC BLUE 41, GOOD
DISCHARGEABILITY
MORE DIFFICULTTO
DISCHARGE
DYE WITH DISCHARGEABILITY
STILL MORE DIFFICULTTO
DISCHARGE
R1 and R2 EWG– good discharge
EDG– Stable dye, poor discharge
OH groups ---H-bonding with azo, difficult to discharge
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DISCHARGING AGENTS
MOSTLY- REDUCING AGENTS---???
• Sodium sulphoxylate formaldehyde (CI Reducing Agent 2, Rongalite C)
since 1905
• Water-soluble zinc sulphoxylate formaldehyde (CI Reducing Agent 6)
• Water-insoluble calcium sulphoxylate formaldehyde (CI Reducing Agent 12)
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Choice of Reducing agent
• Depend on Fabric to be printed
• Dyes used
• Soluble sulphoxylates– Rongalite C- Works better with cellulose
• Haloing effect on synthetic fibres caused by capillary movement of solution along yarns. Hence
insoluble sulphoxylates (mainly Ca based) and thiourea dioxide (CH4N2O2S) are used
• Tin (II) chloride--- can be used but is milder than Rongalite C.
• Amount of reducing agent depend upon
- Dyes to be discharged
- Depth of ground
- Fabric
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REACTION
SODIUM SULPHOXYLATE FORMALDEHYDE
NaHSO2CH2O.2H2O
NaHSO2 + 2H2O
NaHSO2 + CH2O +2H2O
NaHSO4 + 4H
Ar-N=N-Ar’ +2 SnO2 + 4HCl
Ar-N=N-Ar’ + 4[H] ArNH2 + Ar’NH2
TIN CHLORIDE
+ 2SnCl2 +4H2O ArNH2 + Ar’NH2
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THICKENERS
• Should be stable to reducing agents
• Low-viscosity thickeners and a high solids content
• Nonionic locust bean gum ethers, sodium carrageenates, starch
ethers etc.
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Enhancing “whiteness” of discharged
ground
• White discharges are usually improved by addition of TiO2 or
ZnO.
• Optical brightening agents can be used
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White Discharge style using direct
dyes
• Sodium sulphoxylate formaldehyde (Rongalite C) is the most widely used
reducing agent in discharge printing
• Recipe
• Rongalite C- 50-150gm
• Water – 230gm
• Starch paste- 535-455gm
• Titanium dioxide/zinc oxide- 100gm
• Glycerine/urea- 60gm
• Dye--- Print---Dry--- Steaming (100-1020C) for 5-10mins
• Light Soaping
• Dyefixing if required
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Coloured discharge on direct dyed cotton using vat
dyes
•Vat discharge on direct ground is an ideal system
in which the reducing agent (Rongalite C)
performs bothe the functions i.e. discharging the
direct dye and reducing the vat dye for fixation
•The ground direct dye should have excellent
dischageability so that at the printed portions it
is completely destroyed and the proper hue of
the vat dye is formed at the printed area.
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APPLICATION PROCEDURES
VATDISCHARGES ON CELLULOSIC FIBRES
• The coloured ground is applied using selected reactive dyes
• After printing, the prints are steamed for 5–8 min at 102–104°C in an air-free
steamer
• Washing and aftertreatment are carried out immediately
• For vat color discharges, the first two boxes of the washer are used for oxidation of vat
dye
• Oxidation is done at 40–50°C with hydrogen peroxide
• Hot soaping is followed
PADDING SOLUTION (REACTIVE DYES)
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Recipe
Chemical Parts
Rongalite C 100-200
NaOH (50%) 50-200
Water 200-20
Thickener 645-575
OBA 5
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OPEN WIDTH WASHING
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PAD STEAM MACHINE
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RESIST
PRINTING
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RESIST PRINTING
STYLE
 Dyes of great chemical stability, which could not be discharged, can be resisted to give
prints of high fastness standards.
 The resisting agents function either mechanically or chemically or, sometimes, in both
ways.
 The mechanical resisting agents include waxes, fats, resins, thickeners and pigments, such
as china clay, the oxides of zinc and titanium, and sulphates of lead and barium.
 They form a physical barrier between the fabric and the colorant.
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 Chemical-resisting agents include a wide variety of chemical compounds,
such as acids, alkalis, various salts, and oxidizing and reducing agents.
 They prevent fixation or development of the ground colour by chemically
reacting with the dye or with the reagents necessary for its fixation or
formation.
 Not only must a resisting agent be able to prevent the fixation of the ground
colour, but it must also be capable of surviving the actual dyeing process.
 Hence, materials that are not too readily soluble in water are preferred
 For dyeing, Nip padding is usually preferred to immersion (slop)
padding.
RESIST PRINTING
STYLE
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 Some thickening of the pad liquor may be necessary to increase the volume of
liquor carried on to the fabric.
 The temperature of the dye solution must also be kept low
 it is often necessary to dry the fabric immediately after application of the dye, to
prevents partial dissolution of paste contents and their diffusion towards non
printed areas.
NIP PADDING MANGLE
REQUIREMENTS
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USE OF A HORIZONTAL PADDER
 The horizontal padding mangle may be used to apply the dye solution to the printed fabric
 Here also, the contact time between the fabric and the dye solution can be minimized
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RESISTS UNDER REACTIVE DYES
 Since reactive dyes are fixed under alkaline conditions, nonvolatile organic acids can
be used as chemical resists
 Examples - tartaric or citric acid and acid salts like monosodium phosphate
 Thickeners used should be acid-resistant
 Hydroxyethylated and methylhydroxyethylated cellulose ethers, locust bean gum,
etc. are suitable
 One of the problems is – these prints are colorless
 Hence fugitive color such as CI Acid blue 1 or FBAs can be added
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RESIST PASTE RECIPE
 After the print has been dried, it is followed by nip padding or padding with
a reactive dye solution
 If contact time between the liquor and the fabric is more, acid concentration
should be increased to 80 g/kg
 Long immersion times should be avoided
 After padding, dry, steam (2-10 min ) and wash (boil)
CITRICACID
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PADDING SOLUTION
COMPOSITION
RESIST SALT
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COLOURED RESISTS UNDER REACTIVE
DYES
WITH PIGMENTS
1. Preprint with pigment paste containing acid
2.Pad with reactive dye, after intermediate drying, or overprint without
drying
3. Steam for 2–10 min according to the reactivity of the dye used
4. Wash-off
5. Dry.
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RESIST PASTE FORMULATION
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PIGMENT
PRINTING
• The cheapest and simplest printing
method
• More than 50% of all textile prints are
printed by this method
• Insoluble pigments, which have no affinity
for the fibre are used
• They are fixed on to the textile substrate
binding agents (binders)
• Washing is not needed after printing
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COMPONENTS OF PIGMENT
PRINTINGSYSTEMS• Pigment dispersions
• Binders and crosslinking agents
• Thickeners and auxiliary agents giving the
required rheology
• Catalysts
Pigm
ent
Printi
ng
Recip
e
Pigme
nts
Bind
er
Fix
er
Catal
yst
Emulsi
on
thicke
ner
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PIGMENT
DISPERSIONS
• These are generally synthetic
organic materials
• Inorganic ones –
• Carbon black,
• Titanium dioxide (white),
• Copper and aluminium alloys (for
metallic bronze)
• Iron oxide (for browns)
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IMPORTANT PIGMENT
CLASSES
• Azo pigments (yellows, oranges, reds)
• Naphthalene, perylenetetracarboxylic acid,
anthraquinone, dioxazine and quinacridone
(very fast and brilliant oranges, reds and
violets)
• Halogenated copper phthalocyanine
derivatives (blues and
greens).
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• Pigments are ground in a grinding mill in the
presence of suitable surfactants till they acquire
an optimum particle size of 0.03–0.5 μm.
• If the pigment is not fine enough, the prints are
dull and grey
• If they are too fine - loss of covering power
and
colour intensity (less than the wavelength of
visible light)
• The dispersion medium is water for water
based pigments (20-45%)
PIGMENTS
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BINDER
SYSTEMS
• Binder
is
a polymeric
film-forming
substance
• It
prod
uces
dimension
ally
a
thre
e- linked
net
work
to hold
pigment
particles
on
the
textile
• The
li
nks
are formed
during‘curing’ or ‘fixing’
process
• Curing involves dry
heat and a change in
pH

• It results in eitherself-
crosslinking
or reaction with
suitable
crosslinking agents
• The degree of crosslinking
should be limited
• Otherwise the polymeric
network may becoming
too rigidly bonded (losing
extensibility/flexibility)
BINDER
SYSTEMS
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IMPORTANT CRITERIA FOR A
DURABLE 3-D
BINDER FILM
• Transparency
• Elasticity
• Cohesion and adhesion to the substrate
• Resistance to hydrolysis
• As little thermoplasticity as possible
• Absence of swelling in the presence of dry-
cleaning solvents
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CHEMISTRY OF
BINDERS
• Generally addition copolymers
• Formed by emulsion copolymerisation,
leading to
a product with 40–45% binder
dispersed in water
• The size of dispersed polymer particles is
120-300 nm
• Low flammability (no solvent)
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WHAT HAPPENS TO BINDER
AFTER PRINTING?
• During drying, a film is formed from
the dispersed binder in two stages:
• Flocculation (or coagulation) and
coalescence.
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MECHANISM -
BINDER
• During the first stage of film
formation, water and surfactants
are removed from the binder by
absorption and evaporation
• The dispersed solids coagulate to form
a gel-like layer of very tightly packed
‘balls’, which have only poor solidity
and adhesive properties
• These coagulated particles can be
brought back to their original form
by rubbing them with water
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• Second stage- Gel particles flow together to form
a continuous film
• The lowest temperature at which a film can be
formed is usually around 5°C for pigment
printing
• Poly(butyl acrylate), for instance, can form a film
at 0°C
• Polar polyacrylonitrile (PAN) is a very poor film-
former even at high temperatures
MECHANISM -
BINDER
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COPOLYMER AS
BINDER
• A useful film would need to be
produced by copolymerization
• The ratio of butyl acrylate : acrylonitrile
in the range 3:1–5:1 will give a film with
room temp softness
• Too hard a film does not have desired
flexibility
• Too soft a film has poor fastness to dry
cleaning (swells)
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CROSSLINKING
• Cross linking provides elasticity
and improved adhesion of the
film to the substrate
• The crosslinking reaction produces
covalent bonds which are resistant
to hydrolysing agents (washing
liquors, body sweat, industrial
atmospheres)
• The reaction should be activated only
during fixation
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CROSS LINKING
REACTION
• Use of N-methylol groups is done to
effect crosslinking under hot dry
conditions (in acid media)
• Reaction of methylol groups with each
other or with hydroxyl groups which are
also present in cellulose or in the binder
copolymer, takes place
• Water is a byproduct of the reaction
• Hence, hot dry air (130-150oC) is suitable
• Steam has adverse impact on cross
linking
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CONSTITUTION OF
BINDER
• The binder molecule is prepared such
that it contains about 2% N-methylol
groups evenly distributed along the
chains
• This is done by copolymerizing
monomers such as Methylol acrylamide,
Methylol methacrylamide ( or
derivatives) with the main monomers
(such as acrylic acid esters, acrylonitrile
or butadiene)
• Higher % of methylol groups would make
the chains too rigid, resulting in poor
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METHYLOL
ACRYLAMIDE
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EXTERNAL
CROSSLINKING AGENTS
• External poly-N-methylol compounds
can be added to enhance crosslinking
• Especially useful for hydrophobic
materials
• Water-soluble derivatives of tetra- to
hexa-methylol melamines are
preferred (melamine formaldehyde
resin)
• Act mainly as adhesive agents between
the textile and binder
• Also contribute to the crosslinking at the
surface of the binder film
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THICKENING
SYSTEMS
• The colloidal polysaccharide thickening agents
are not suitable for pigment printing
• (Examples starch, cellulose ether, alginates or
locust bean gum)
• Their flow properties are unsuitable and they
form brittle films
• The prints produced with such thickeners are
dull with poor fastness and a harsh handle

PROPERTIES OF PRINT PASTES• Pseudoplastic (shear-
thinning) pastes are
suitable for pigment
printing
• Such pastes do not
penetrate deep down
into the textile fabric
• Paste on surface provide
better color value, a
sharp mark and
brilliance of color
• Also handle is better as
the fibres and yarns are
not bonded by binder
and cross linking

EMULSION
THICKENERS• The most suitable are the emulsion
thickeners
• White spirit/water emulsions (o/w
type) are
of
the
greatest practical
interest
• Composition -
 70-79% hydrocarbons in the
disperse phase
 0.5-1% of nonionic emulsifiers
with HLB in
the region 12-15
 29-20% of water in the
continuous phase.

PROS AND CONS
• All the components, except the
emulsifying agents, evaporate
completely, leaving no residues
• There is no hardening of the handle of
the textile due to thickener
• Drying of the printed textile is quicker as
the evaporation enthalpy for white spirit
is about 25% of that for water
• This improves the printing speed and
hence the production
• Mineral oil products are too valuable to
be used just as print paste thickening
agents

• The emission of organic substances into the
atmosphere is not desirable
• Recovery of the white spirit from the exhaust gases by
cooling apparatus and batteries of charcoal filters is
too complicated and too expensive
• 0.4% by volume of white spirit in air is flammable
• In India, Kerosene oil is used, which is flammable too
• Hence print pastes based on white spirit/kerosene are
being phased out
PROS AND CONS

SYNTHETIC-POLYMER
THICKENING AGENTS
• Synthetic thickeners are polyanionic compounds derived
from acrylic acid and maleic anhydride
• Have rheology similar to that of emulsion thickeners and
extremely low solids content
• Have very high swelling power (maximum at pH 9-10)
• Ionization increases solvation in water
• Ionization creates charged groups which cause repulsion and
hence the material expands in dimensions
• This brings about a hundredfold expansion in size

• These are sensitive to presence of salts, hard water, acidic pH etc
• On drying, it leaves a residue (0.5-1%)
• The dry thickener film is hard and inflexible
• Has adverse effect on handle of printed material
• It can be compensated by use of softeners
• Neutralizing agent is ammonia, removed during drying
• The carboxylic groups provide the required acidity for binder
reaction. No additional acid liberating agent required
• Emulsion thickener based pastes need about 0.5% potential acid,
such as diammonium phosphate (DAP), for required acidity
SYNTHETIC-POLYMER
THICKENIN
G AGENTS

COPOLYMERISING 1 MOL ACRYLIC ACID
AND 0.01MOL DIVINYLBENZENE TO
FORM A THICKENINGAGENT

PIGMENT PRINTING
PASTES
• The amount of binder needed in a print paste is related to
the amount of pigment
• Even the minimum amount of pigment requires a binder film at
least 5μ thick
• A minimum of about 7% binder (of about 40% solid content)
in the paste is needed
• Additional pigment needs about 1.5–2 times its own mass of binding
substance (25% pigment emulsion and 40% binder emulsion–
Pigment : binder, 1:2.5 TO 1:3)
• For hydrophobic materials (including polyester/cotton blends),
another 0.5–1% of external crosslinking is added

RECIPE
REDUCTION THICKENER
(EMULSION BASED)
1. Emulsion
thickener
Water- 10parts
Binder- 10 parts
Kerosene oil- 79
parts Emulsifier
– 1 part
Total – 100parts
2.
Print
Paste
Pigm
ent --
X
parts
Urea
-- 5
parts
Di ammonium phosphate (DAP) – 1
part
Binder -- As required ( Added only for
dark shades) Cross-linker – In case of
synthetic fibres 1 part Emulsion
Print– Dry (800C, 3-4 mins)—Cure
(1500C for 3-5 mins)

Synthetic THICKENER
(WATERBASED)
1. Aqueous synthetic thickener paste
Water- 90-95 parts
thickener- 9-4 parts
Ammonia- 1 part Total – 100parts
2. Print Paste
Pigment -- X parts
Binder -- As required ( Added only for dark shades) Softener – 1part
Crosslinker– In case of synthetic fibres 1 part Antifoamer– If required 0.5
parts
Thickener paste -- Tomake 100 parts

POSSIBILITIES AND
LIMITATIONS
Advantages
• The most economical printing process and
allows maximum output of goods
• Elimination of washing-off, quick sampling
and high printing speeds
• Have very good fastness to light and good
general fastness properties
• Can be applied to all substrates (including glass
fibres, PVC and imitation leather)
• Well suited for colour resist effects
• Presents the fewest problems for the printer
• Ecologically, is more acceptable than any
other system (if not using white
spirit/kerosene)

Limitations
• The fastness levels of medium- or dark-
coloured prints on materials made from
polyester, acrylic and wool are not
adequate
• The handle of the printed goods is
often unduly hard because of the
large amounts of external crosslinking
agents
• Pigments are sensitive to crushing during
roller printing
• In overprinting, the second paste has little
effect: the paste
first printed determines the colour
• No pigment print is completely fast to dry

Types of transfer printing
• Sublimation transfer
• Melt transfer
• Wet transfer
• Film release

Textile Printing Process Guide

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Textile Printing Process Guide