Dyeing, printing & processing defects

SUBMITTED BY :
RAJEEV SHARAN/ ROLL NO-23/ DFT-05

Common causes of dyeing defects
1.The material is not well prepared for dyeing and printing
 Material having dead fibres or other defective fibres
 Left over of Chemicals after bleaching etc.
 Material not properly desized.
 Material not properly mercerised.
 Absorbency of the fabric not proper
 Sticking of insoluble material on the fibres
 Impurities are not removed properly
 Uneven heat treatment.

2.Water Quality not Proper
 More Hardness of water
 Water has metal ions such as iron.
 pH of water not proper
 Water having more chlorine
3. Due to Shortcomings in making Dyeing Solution
 Improper weight ratio of colours, material and chemicals.
 Improper material to water ratio
• Improper filtering of concentrated colours
4. Due to Shortcomings in the dye machinery
• Coming out of Dye liquor during dyeing
• Defective instruments controlling temperature, pressure speed etc.

Influence of Fiber Related Properties on
Dyeing behavior

 Un-drawn or partially oriented yarns - Easy to dye. – Low Molecular
orientation –Rapid dyeing.
 Drawn material – higher Molecular orientation – dye slowly.
 Synthetic fibers are produced at various draw ratio (low – staple fibers to
high values – draw bulked yarn)
 Material having relatively small differences in their rates of dyeing – but
very considerable differences in color. .

• The differences arise in the strike stage of the dyeing
process,
Why uneven dyeing occurs?

1. Improper leveling of dyes -
– Effectiveness of the redistribution of dye during the subsequent leveling
stage.
– If the leveling action is poor, as in carrier dyeing at 98°C or when dyes of
poor migration properties have been used,
– The effects of small variations in spinning and drawing conditions may
be expected to show as variations in color in dyed materials.

For Staple Fibers,
– The problem is more difficult, but of less practical significance,

2. The Effects of Heat and Tension

• Yarns and fibers are subjected – heat or of mechanical stress or both
• The effects of variation in temperature or in tension during heat
treatment are more severe .
• And can produce relatively large color differences if the differently treated
fibers are dyed in the same bath.
• Reduction in rate of dyeing between. 130°C and 150°C, followed by
leveling off.
• Uniform tension over the yarn during H.S, leads to perform better leveling
off.

3. The Effects of fiber lubricants and spotting agents

 Fibre Lubricants -- Source of variation – can affect quality of the dye bath
 After long storage , they can also produce significant local alterations in
the rates of migration of dyes in the fibre
 Spotting agents sometimes applied to loom stains by weavers, and
produce localized dark spots that show up after dyeing.
 For this reason, the use of such spotting agents outside the dye works is
to be discouraged.

4. The Effects of Fiber Structure

• Drawing the fiber - Growth of highly ordered regions – oriented along the
axis of fiber
• Heat treatment induces further growth in these highly ordered regions at
the expense of less ordered regions.
• Number, size, spacing and distribution of these highly ordered regions

That these influence, the number and arrangement of chain folds in the
polymer.

5. Carriers

 Fibre becomes more open structure or less ordered regions around the
structural dislocations contain spaces just large enough to admit the
molecules of disperse dyes under the influence of thermal agitation.
 Thermal agitation – leads to increases in the rate of diffusion of dyes at
Tg,
 Suitable carriers are used to locate uniform striking of dyes.

6.Barre Effects: Differences in the rate effect.
• Differ in the fractions of their internal volumes that are available for the
absorption of dyes
• Differences in the dye uptake during initial dye transfer,
– Rate of diffusion
– Differences in the accessibility of this available region.
– Accessibility – a property of the less ordered regions of fibre structure.
– Availability – associated with an internal area.
• How to Reduce barre effect ?
– High temperature leveling treatment, possibly in the presence of a small
amount of a suitable carrier
– May increased by the presence of carrier during the early stages of dyeing.
– Drawing – hot stretching produce decreases in both availability and accessibility
as the general orderliness of the fiber structure increases.

7. Ring Dyed Material in Synthetic yarn

• Most of the dye present on the fiber surface layer less than one third of
the radius of the fiber in depth.
• Causes: dyeing time, bath temperature or the level of carrier addition to
the bath is inadequate.
• Even high temperature dyeing can be ring dyed if insufficient time has
been allowed for the full penetration of slowly migrating dyes.

Some common dyeing problems
1. Un levelness
• cause – improper dyeing conditions.
• Ending problems

causes countermeasures

1. unstable dye dispersion 1. select dyes with better dispersion stability, use efficient
dispersants .
2. unsuitable dye combination 2. Attention should be given to uniform dye behaviour .
3. wrong dyeing program 3. Optimum dyeing process should be followed .

Cloudy dyeing

Causes Countermeasures
1. inadequate pre-treatment 1. select optimum conditions and
chemicals
2. channelling due to irregular winding 2. pay particular attention to winding of
the material
3. poor circulation of the goods due to 3. adjust the machine more carefully
interruptions, knots, etc.
4. too much foam in the dyebath 4. use antifoams, e.g. Antimussol brands
5. wrong dyeing programme 5. Optimum dyeing process

Pale Areas

1. Inadequate Pre-treatment 1. Select optimum conditions and
chemicals
2. Air pockets in the material 2. Use special chemicals, e.g. wetting
(e.g. cheeses) agent / defoamer combinations, or
greater pressure

2. Unlevelness
cause: due to material.
Barriness
1. Variations in temperature during 1. -adapt dye selection
fibre manufacture(texturizing), draft - select higher dyeing temperature
differences - select suitable carriers and
chemicals
- possibly set fibres at a higher
temperature.
2. Variations in the density of the 2. Relax material thoroughly
material (weaving, knitting)

3. Unlevelness
cause: due to other reasons.
Skitterness

1. inadequate pretreatment (e.g. desizing) 1. pay attention to perfect
pretreatment
2. fibres of different origins in the material 2. pay particular attention to
the appropriate dyeing
process and programme
3. poorer solidity on both components of
fibre blends
4. irregular thread tension during weaving
or warp knitting

Listing

Causes Countermeasurement
1. Inconsistent setting temperature 1. select special dyes (small-
moleculed)
2. Irregular tension in the material due 2. relax material thoroughly
to weaving or warp knitting
3. Poorly wound material 3. pay particular attention to
winding
4. Rolled in selvedges due to irregular 4. -set the goods
tension in the material (weaving, warp - size the selvedges
knitting) - check the weaving or
knitting machine

Pale areas after dyeing.


effect of aggressive vapours -efficient ventilation of vapours and
(e.g. acid, chlorite, formaldehyde) gases
- avoid contact with dangerous
substances

•4.Reproducibility.
Deviation of shade
Causes Countermeasure
1. dye sensitivity to hydrolysis, 1. -select dyes carefully, control pH
reduction, electrolyte exactly
(buffer system)
- pay attention to stability of dye to
electrolytes
2. dye sensitivity to metal ions in the 2. use suitable sequestering agent
dyebath
3. dyes of different chemical 3. pay particular attention to selection
constitution affect each other (rare) of dyes and chemicals
4. dye buildup affected by chemicals 4. carry out lab tests
(retarding effect)

Causes Countermeasure
5. different dyeing programmes 5. pay attention to consistent dyeing
conditions
6. different liquor ratios 6. pay attention to consistent dyeing
conditions
7. dye shows differences in standard 7. check supplies
conformity
8. unsuitable dye combination 8. pay attention to behaviour of
individual elements
9. sedimentation of liquid dyes 9. stir before removal from container
10. bath exhaustion affected by 10. adapt dye selection and process
reserve of adjacent fibre

5. Fastness properties
Unexpectedly poor light fastness

causes countermeasure

1. carrier residues on fabric 1. repeat thermo fixation (at higher
(inadequate thermo fixation) temperature)

2. stained adjacent fibre 2. adapt dyeing process, select
appropriate dyes

3. catalytic fading due to unsuitable 3. adjust dye selection
dye combination

Unexpectedly poor wet and rub fastness


1. thermomigration due to finishing and 1. adjust dye and chemical selection
softening chemicals

2. inadequate dye fixation due to too 2. Optimize dyeing process, reduction
short dyeing time or too low fixation clear
temperature

3. stained adjacent fibre 3. Improve dyeing process

6. Spots, marks
Precipitates in the dye-bath

1. dye precipitates due to poor 1. - pay special attention to dispersing
dispersion or dyes with poor dispersion instructions
stability - pay attention to dye selection
(dispersion stability)
- use dispersants
2. dye crystallization due to variations 2. pay attention to perfect liquor
in temperature in the dyebath circulation
3. coloured spots due to dye deposits 3. pay attention to cleanness in the
on the machine machine

causes countermeasure

4. use of volatile carriers 4. select suitable carriers, use overhead
heating in the machine

5. silicones in the dyebath 5. use silicone-free de foamers

6. unstable chemicals 6. select suitable chemicals

7. oil and spinning preparations 7. thorough pre treatment

8. oligomers in the dyebath 8. drop dyebath hot, shorter dyeing time,
use special chemicals

• Singeing droplets
1. as a result of singeing before dyeing, 1. singe after dyeing
fibre tips exhibit higher affinity for dyes .

• Change of shade (e.g. blue spots in brilliant red shades)

1. dye is sensitive to metal ions 1. use a sequestering agent
2. alkali residues 2. neutralize the goods

3. finishing chemicals 3. scour and select finishing chemicals
carefully

• Dark spots

1. solvent residues from pre treatment 1. complete removal of solvents

• Specks

1. contamination of the material by 2. do not store material near dyes; use
dyestuff dust low dusting dyes

• Dirt spots

1. contamination of the material by 1. pay attention to clean machines and
rust, oil, graphite, etc. clean working methods

7. Appearance of the goods
• Dimensional stability (shrinkage)

1. insufficient relaxation during pre 1. adapt relaxation and setting to
treatment material in question
2. Inadequate setting of material 2. adapt relaxation and setting to
material in question
3. lengthwise distortion caused 3. adjust dyeing machine to material
by dyeing machine

• Creasing

1. inadequate pre treatment 1. select optimum pre treatment conditions
(scouring, relaxation, setting)
2. due to quality of goods (structure, 2. adjust dyeing machine to material, select
e.g. tightly woven fabric, weight) correct setting temperature, adjust stenter
correctly
3. poor suitability of dyeing machine 3. select more suitable dyeing machine

4. too heavy batch of fabric 4. add a lubricant, e.g. lmacol brand

5. incorrect loading of machine 5. add a lubricant, e.g. lmacol brand

6. dyeing process (heating, cooling) 6. adjust temperature programme, add a
lubricant, e.g. lmacol brand

•Chafe marks


1. mechanical friction due to overloading 1. add a lubricant e.g. lmacol brand

2. rough patches in the machine 2. add a lubricant e.g. lmacol brand

3. stationary material in the running 3. add a lubricant e.g. lmacol brand
machine (knots)

4. too high machine speed 4. add a lubricant e.g. lmacol brand

•Stitch distortion (knits)

1. inadequate pre treatment 1. selection optimum pre treatment
(relaxation, setting) conditions
2. mechanical effects, e.g. passage of 2.straight seams along weft and stitches
goods in machine, squint seams

•Moire effects (on beam)

1. inadequate pre treatment 1. -select suitable setting conditions
(setting, rolling up) - roll up carefully

• Lustre
1. physical change in fibre due to local 1. avoid prolonged contact of stationary
pressure and high temperature on material material with the hot machine
2. excessive setting 2. select suitable setting temperature

• Handle
1. unfavourable conditions between machine and 1. select optimum conditions
material
2. inadequate pre treatment 2. can be corrected during finishing
(relaxation, setting)
3. wrong dyeing programme 3. can be corrected during finishing
(temperature / time)

• Pilling (staple fibres)

1. susceptible fibre origin (also in fibre 1. select fibres carefully, use selected
blends) softeners
2. inconsistent dimensional stability due 2. setting
to shrinkage (fibres protrude from fibre
bundle)

8. Thermosol dyeing problems
• Listing
1. one-sided liquor feed into the 1. check injection pipe or mount a distribution plate
trough
2. different nip roller pressure 2. check rollers (pickup) regularly
3. unlevel migration in 3. -check temperature and air current over the entire
intermediate drying width in the drier
- avoid migration by using lowest possible pickup
and a suitable migration inhibitor.
Select dyes with little tendency to migrate.
4. uneven thermosolling or fixation 4. check fixation units regularly with thermopaper or
of dyes due to temperature temperature sensors
differences - use more reliable dyes with as little sensitivity as
possible to temperature deviations

•Two-sidedness
1. deflecting roller touched on 1. check injection pipe or mount a distribution plate
one side only
2. deflecting roller stationary 2. check rollers (pickup) regularly
3. pad rollers not the same 3. - check temperature and air current over the entire
width in the drier
- avoid migration by using lowest possible pickup and
a suitable migration inhibitor.
Select dyes with little tendency to migrate.

4. uneven drying from side to 4. - check fixation units regularly with thermopaper or
side temperature sensors
- use more reliable dyes with as little sensitivity as
possible to temperature deviations

• Ending

1. dye substantivity 1. - with lndigosol dyes add Lyogen WL
- use a smaller volume of liquor
- dye at higher fabric speed
2. dye sedimentation 2. - keep the liquor in motion
- keep the temperature below 35°C

• Dark or pale selvedges


1. one-sided liquor feed into the trough 1. check liquor feed

2. narrow goods impregnated on a wide 2. move to a suitable machine
padder
3. worn rollers, rollers bend due to over 3. check the nip pressure, reduce pressure if
compensation necessary, change rollers if necessary, chick
hydraulics
4. varying drying conditions over the width 4. check the air jets and circulation
of the goods
5. alkali residues in the goods 5. add acetic acid to the padliquor for pH 5-6

• Barry dyeings

1. uneven jet pressure in the drier 1. check the air jets

2. inadequate evenness of tension in drier, 2. check guidance of goods in drier
crease formation

3. alkali residues in the goods 3. add acetic acid to padliquor for pH5-6

Defects in Sulphur Dyeing

• Uneven Dyeing and Oxidation Marks

This may occur due to:

a. Lower strength of sodium sulphide
b. Using improper amount of sodium sulphide.
c. Sodium sulphide does not wash off fully after washing.
d. Variation in temperature.
e. If colours are not dissolved properly, or colours are not of good quality
f. If the chemical used for oxidation is not of good quality
g. Fabrics are not worked upon properly at the time of dyeing.

Bronziness

This defect normally occurs in heavy shades. Given below are the reasons:

1. More time gap between dyeing and washing
2. Using more of less strength sodium sulphide
3. Using more salt.
4. Oxidiser doesn't get washed off properly during washing
5. Sodium sulphide doesn't get washed off properly during washing.
6. More presence of iron and copper ions in water.

• Poor colourfastness to rubbing
the reasons are :
a. type of colour
b. Lower strength of sodium sulphide
c. Poor absorbency of the fabric
d. Fabric is not washed properly
e. The quality of soap used for washing is not proper
f. Dyeing bath made of iron instead of steel
g. Frequent addition of colours and chemicals
h. Using Cationic finishing agent in finishing also lowers the colourfastness to rubbing
i. Improper colour solution, Improper material to liquor ratio etc.

Roughness in Fabric
The reasons are:
1.Using more amount of sodium sulphide that doesn't get washed off during washing.
2. Heavier shade
3. Improper washing
4. Not using anionic softening agent in finishing
5. Not using wetting agent.

Tendering

Tendering in the fabric takes place because sulphur is converted into sulphuric acid after
oxidation which is harmful for the cellulosic fibers. This defect can occur on account of not
proper washing of the fabric after dyeing which results in retaining of sulphuric acid on the
cloth.

Defects in Dyeing with Reactive Dyes

• Colours are not fast to washing, Abrasion; Staining in the fabric when
transporting from place to the other, water marks on the fabric .
• Bleeding in colours during washing, abrasion .
• The fabric has been dyed in darker shade, uneven dyeing .
• Uneven dyeing, marks of water, marks of colours.
• The fabric has become stiff and rough after dyeing .
• Colour staining of fabric, uneven dyeing .
• Colour staining in fabrics of darker shade, uneven dyeing

Defect in Vat Dyeing
• Poor Colorfastness in Vat Dyeing
the reasons
• Frequent addition of colors in the dye bath to match the shade. It disturbs the
equlibrium between colors and chemicals.
• Improper oxidation
• Improper washing
• Some peculiar colors such as blue and brown also leads to this defect.
• Hardness in the water used
• Mixing of incompatible colors
• Usage of large quantities of reducing agent and alkali
• Improper temperature
• Improper wringing of the cloth
• Faults in the machine
• Not using essential chemicals such as dispersing agent or leveling agents.
• Dyeing in a finished cloth ( Resin or Silicon Finish)

•Listing defects in vat dyeing

The reasons are:
• Improper batching.
• Non Uniformity in the selvedge
• Redyeing of the fabric
• Foam on the two sides of the jigger.
• Slippage of the fabric from the roller during dyeing.
• Shortcomings in the machine such as malfunctioning of guide roll,
expander roller or improper squeezing.
• Improper filteration of the colors, improper circlation of the liquor during
dyeing. Difference in temperature of liquor in the centre and at the ends.
• Mixing of colors which are not properly compatible.
• Improper singeing

Uneven Shade (shading
OR listing)

• differences in the shade of
a fabric from edge to edge
or one end of a fabric to
the other Called selvedge-
to-selvedge (or selvedge to
center) shading or end-to-
end shading respectively.

MAIN CAUSES:
— Often caused in jig dyeing through difference of temperatures between
the selvedges & centre of the batched up fabric on the jig roller.
— by uneven batching of the cloth on the roller.

MENDING
Non-mendable.

Minor Major Serious
Not reckoned Up to 15 cm along > 15 cm along the
the length length

Patchy/ streaky/ uneven
dyeing
• The fabric is characterized by
an area of light or heavy dyeing
along and across the width of
fabric. Also, light or heavy dyed
patches or light and dark
streaks appear on the fabric. It
also includes shade variation
and light or heavy dyeing on
selvedges.

MAIN CAUSES:
• Improper scouring.
• Cloth fed to the dyeing machine not crease free.
• Proper time & temperature not given in dyeing.
• Defective padding roller.
• Fluff or thread on the fabric or in the color in the dye stuffs.

MENDING:
Non-mendable.

Minor Major Serious
Up to 1 sq. cm 1 sq cm to 6 sq. cm >6 sq cm

Shade Bar

• shade change in fabric
which appears as a
horizontal selvedge-to
selvedge change. Caused
by a filling change (new
filling bobbin) or loom stop
and subsequent start up

MAIN CAUSES
• Improper scouring
• Defective padding roller
• Proper time & temperature not given in
dyeing.
• Difference in count/ fiber composition
of weft yarn.

MENDING
Non-mendable.

Minor Major Serious
Not reckoned Up to 15 cm along the length > 15 cm along the length

Dyestuff Stain
• An unwanted color mark on a fabric
qualifies as a dye stain.

MAIN CAUSES:
• Improper mixing of dye stuffs.
MENDING:
Non-mendable.

Minor Major Serious

White Spot
• The fabric is characterized by a white spot on
otherwise well dyed adjacent fabric.
MAIN CAUSES:
• The mixture used for dyeing is not
compatible.
• Colors not properly dissolved.
• Proper time & temperature not given in
dyeing.
MENDING:
Non-mendable.

Minor Major Serious

Color Crocking
• color in a dyed fabric which rubs off
rather easily onto other fabric
surfaces.
• Causes-
– May be caused by inadequate
soaping at the completion of
dyeing cycle.
– Due to faulty or improper
dyeing procedures, OR
preparation of the fabric prior
to dyeing, OR imperfections in
the fabric itself.

• Most frequently occurring
imperfections – result
from dyeing processes

Tender spots
• Places in the fabric which
have been excessively
weakened, usually by
exposure to processing
chemicals. When the
entire fabric is weakened,
it is referred to as Tender
goods. Also occurs in
printing and finishing
procedures.

Stained, streaked
• A discolored area on
the cloth. Caused by
foreign matter such
as dirt, grease, oil or
residues of sizing on
the fabric being dyed

Color bleeding
• loss of color from a dyed
fabric when immersed in a
liquid. Liquid subsequently
becomes colored

Off shade
• an expression referring
to the fact the color of
the dyed fabric does
not match the std.
color or referenced
sample

Barre
• In woven fabrics, a horizontal band off-shaded yarns extending from
selvedge to selvedge caused by differences in filling yarn size or
difference in tension of warp or filing yarns

Defect caused by
hanging thread
• A break in the pattern of the
printed fabric caused by
hanging thread
MAIN CAUSES:
• Loose threads in the fabric not
trimmed before printing.
MENDING:
Non-mendable .

MINOR MAJOR SERIOUS
Not Prominent Not
prominent reckoned

Misprint or absence of
print

• A misprint can be one or more
of the following
– The printing is not per as required
the required design.
– The outlines and the colors in the
design are not remain at its proper
place.
– A bare place without any printing.

MAIN CAUSES:
• The design is not set properly.
• Unequal pressure at different places during printing.
• Design not properly engraved/ screened.
• Improper cloth used for printing.
• Improper stitching of cloth.
• Cloth fed with uneven tension to the printing machine.
• Improper storage or cleaning of the screen.
MENDING:
Non-mendable.

Minor Major Serious

Uneven printing
(tinting)

• In a printed fabric the
design at one place is bold
as required, while at other
place the same is hazy ,
light and unclear.

MAIN CAUSES:
• Uneven pressure on printing rollers & doctor blade.
• Uneven lapping of central drum in printing machine.
• Diameter of printing roller is uneven.
• Printing paste level not maintained.
• Defective doctor blade.
• Printing table is not proper.
MENDING:
Non-mendable.

Minor Major Serious

Blurred (dark) patch
• Unwanted blotch or bar in a
printed/ dyed fabric results in
a blurred patch

MAIN CAUSES:
— Improper scouring.
— Unclean doctor blade & printing roller.
— Doctor blade not properly aligned.

MENDING
Non-mendable.

Minor Major Serious
the length length

Water mark

• An unwanted ripple effect/ light
mark produced on the fabric is
known as water mark.

MAIN CAUSES:
— Improper scouring.
— Surface pressure of one layer on another.
— Contamination with water prior to tinting or dyeing on the padding
mangle resulting in a reduction of intake of dye liquor.

MENDING
Non-mendable.

Minor Major Serious
the length length

Misfits
• A misfit is a print defect caused
by improper alignment of the
screens. Also known as “out of
registration,” misfits leave
unprinted areas in the design.
For example, a green leaf may
overlap its black outline or
print over another color. Up to
10 % of printed goods
designated as first quality
contain some level of misfit.

Stick-in
• A stick-in occurs when a
small fiber or piece of
lint gets stuck in the
screen opening. The
result is a small pen tip
sized unprinted circle in
the design. A stick-in is
very difficult to see and
often goes unnoticed
during a long run.

Scrimps
• A scrimp defect occurs
when the fabric creases
underneath one of the
screens during the
printing process. The
pattern is then printed
on top of the crease,
leaving a large unprinted
area when the fabric
returns to its relaxed
state.

Wicking
• Wicking, also known as
flushing, occurs when the
printed area bleeds out into
the unprinted area. The result
is a “haloing” or shadowing
effect around the outline of
the pattern design. Residual
salts left in the fabric during
resin finishing and / or poor
fabric preparation often cause
wicking.

Spotting
After printing some
spots occur on
printed fabric

Print color
variation
Can occur due to
uneven roller or
squeegee pressure
while printing paste
is applied

Flipped yarn MAIN CAUSE:
• The part that look like •Insufficient penetration of color paste.
•Treatment after printing is not carried out
scratches because the
appropriately.
warp & weft have
turned upside down

Bleeding MAIN CAUSE:
•Too low viscosity of color paste.
• A printed motif blurs •Too high concentration of dyestuff in print
& as a result the paste.
outline of design •The amount of color paste printed or
appears unclear amount of hygroscopic agent used is too
large.

Blebbiness • A part of printed surface became blebby
with a rough appearance like that of
sharkskin.

MAIN CAUSE:
•Unsuitability of color
paste viscosity.
•Screen mesh.
•Uneven adhesion.

• The printed cloth is piled up after insufficient
Staining during drying or apart of the cloth touches another
steaming during steaming.

MAIN CAUSE:
•Poorly washed
printing table.
•Irregular (high )
steam &
temperature.

Slight touching MAIN CAUSE:
•Slow replenishment of color paste.
• Some area in a motif •Uneven squeegee pressure.
has pale spots. •A squeegee with inappropriate hardness.
•Bad squeegee relay.
•Uneven surface of printing table.
•Inappropriate viscosity of color paste.
•Inappropriate use of
thickener.

• Disfigured designs or overlapped motifs
Poorly adjusted
screen

MAIN CAUSE:
•Inaccurate
adjustments of the
belt-drive and point.

• Designs printed are a little off.
Double printing

MAIN CAUSE:
•Disfigured designs.
•Poor engraving.
•Poor cloth adhesion.

Pressing paste by • A frame mark appears in the printed area.
frame

MAIN CAUSE:
•Poor belt-drive and
frame installation.

Banding
• defect created by the print head’s movement over the substrate.
• If the head is not properly aligned, or if the substrate advances
unevenly, the result is a slight horizontal “band” or line of unprinted
area.
• Banding can be reduced or prevented :-
– with nozzle redundancy and multiple passes by the scanning print
head.
– In addition, banding is naturally reduced by most fabric substrates.

Misfire
• occurs when the inkjet nozzle fails to send a drop of ink onto the fabric.
Similar to a stick-in, the result is a small, unprinted area. In addition to
misfires, nozzle clogging also plays a big role in digital defects.
• When an inkjet nozzle clogs, the pattern may lose some or all of one
colour. Fortunately, the inkjet drop is tiny, and most misfires and clogs
are not seen if the printer has been designed with nozzle redundancy.

Incorrect Fabric Handling
• Fabric handling also plays a role in the creation of defects with digital
printing. Because most digital printers use a scanning head to print
across the width of the fabric, the fabric must remain perfectly still or
the image can be distorted.
• One of the biggest fabric handling related defects occurs when the
fabric buckles or gets wrinkled, causing the scanning inkjet head to
come in contact with the fabric. The result is a nasty ink smear and
possibly a damaged print head.

Defects Description
Fading The loss of colour brilliance through exposure to factors such as
sunlight or cleaning agents.
Frosting A change of fabric colour caused by localized abrasive wear, such as
that occurring at collar points or garment creases.
Fume Fading A change of shade in dyed fabric caused by the chemical reaction of
certain disperse dyes with atmospheric contaminants such as burnt
gas fumes and ozone.
Fuzzy Pattern Design lines in printed fabrics that are meant to be sharp
demarcations of colour but that are muted or blurred.
Migration The transfer of colour from one area of the fabric to another.

Defects Description
Metamerism A phenomenon, also known as flare, that is observed when
materials are viewed under different light sources. The spectral
reflectance curves are not identical, so the viewer sees one color
under one light source (incandescent) and a different color under
another light source (fluorescent).
Off Grain Lacking trueness. In printing, the design is transferred to the fabric
so the design of the fabric is not aligned with the yarns.
Off Register Lacking color alignment. In printing fabrics, the color separation is
imperfect, producing a situation in which the different color
components of the design are not aligned.

Defects Description
Crease Streak Occurs in tubular knits. Results from creased fabric passing through
squeeze rollers in dyeing process.
Depending on the product; usually Major for fashion outerwear,
Minor for underwear.
Color Smear The result of color being smeared during printing.

Color Out The result of color running low in reservoir on printing machine

Back Fabric Backing fabric is often used to cushion fabric being printed. If there
Seam is a joining seam in the backing fabric, an impression will result on
Impression printed fabric.

Mottled Color applied unevenly during printing

Condition wherein the weft and warp yarns do not keep at
Bowing right angles.

MAIN CAUSES:
• Improper stretch during scouring, dyeing or finishing.
• Uneven tension during weaving/ processing.
MENDING:
Non-mendable.

Piling
The entangling of fibers
during washing, dry
cleaning or while being
worn form balls or pills and
stand on the surface of a
fabric and are of such
density that light cannot
pass through them.

MAIN CAUSES:
• Span length not maintained in spinning.
• Broken filament or low twist yarn.
• More abrasion on surface of cloth during processing.
MENDING:
Non-mendable.

MINOR MAJOR SERIOUS
Not prominent Prominent Not reckoned

Askewed or Bias
• Condition where filling yarns are not square with wrap yarns on woven
fabrics or where courses are not square with wale lines on knits.
MAIN CAUSES:
• Improper stretch during scouring, dyeing or finishing.
• Uneven tension during weaving/ processing.
MENDING:
Non-mendable.

Sanforize Pucker

• Fabric will appear wavy or puckering when spread on cutting table.

MAIN CAUSE:
• Results from uneven wetting out on sanforize; usually caused by
defective spray heads.
• Difficult to detect during inspection on inspection machine with fabric
under roller tension.

Pin Holes

MAIN CAUSE:
• Holes along selvage caused by pins holding fabric while it processes
through tenter frame.
• Major> if pin holes extend into body of fabric far enough to be visible
in the finished product.

Crease Mark

• Differs from crease streak in that streak will probably appear for
entire roll.
• Crease mark appears where creases are caused by fabric folds in the
finishing process.
• On napped fabric, final pressing may not be able to restore fabric or
original condition.
• Often discoloration is a problem.
•

Selvedge torn

MAIN CAUSE:
• Usually caused by excessive tension while processing through tenter
frames.

Various finishing processes
Aesthetics finishes Description
Parchmentizing A finishing process to give cellulosic fabrics such
characteristics as transparency, linen-like hand, and texture.
Softening Softening agents are frequently used to improve the hand
and drape of fabric. The most commonly used softeners are
oils, fats, wax emulsions, soaps and synthetic detergents,
and silicone compounds. Silicone compounds produce
relatively durable softening.
Stiffening Some fabrics need to be made stiffer and more crisp than
they would otherwise be in order to meet an intended end
use. Stiffening may be done by any of several chemical
finishes, all applied by pad and either dried or cured. Starch
is widely used but starch finishes are temporary.

Aesthetic finishes Description
Plissé This is a permanent finish, produced on cotton by the
treatment of sodium hydroxide to produce a puckered or
crinkled fabric.
Embossing This is a process to produce a raised design or pattern in
relief on fabrics by passing the cloth between hot engraved
rollers that press the design into the fabric.
Surface/ texture Description
finishes
Napping Napping uses a series of 24-30 cylinders covered with
fine metal wires bent into small hooks, to produce a
thick, raised fiber surface on fabrics produced from
loosely twisted staple-fiber yarns.
Sueding A process similar to napping, it is a mechanical finish
that produces a soft, suede-like surface on the fabric.

Luster finishes Description
Calendering A finishing process producing a flat, glossy, and smooth surface
by passing the fabric under pressure between cylinders.
Ciré Ciré is a highly polished fabric produced by impregnating the
fabric with wax or a thermoplastic material and then passing it
through friction rollers.
Glazing A process that produces a smooth, high polish on the surface of
the fabric.
Moiré A moiré finish is characterized by a soft luster and an optical
effect, which is created by interference between light rays
reflected from the crushed and uncrushed parts of the fabric.
Schreinering A finishing process where the fabric is passed under pressure
between an engraved steel calender roller and a smooth roller.
The engraved roller has 180-360 fine lines embossed.

Luster finishes Description
(optical)
Delusterants A process of dulling the luster of manufactured fibers, yarns, or fabrics
with pigments or chemical treatment.
Optical Optical brighteners are used in finishing to maintain white and bright
Brighteners fabrics. They adhere to the fabric and create an appearance of
whiteness or brightness by the way they reflect light; they absorb
ultraviolet light and reflect it as visible blue light.
Care finishes Description
Durable Press This finish provides garments with shape retention, durable pleats and
pressed creases, durably smooth seams, and wrinkle resistance.
Soil Release A finish that increases the absorbency of a fabric, and which makes it
easier to remove soil and stains in washing.

Care finishes Description
Stain- and Soil- Stain and soil-resistant finishes reduce the rate of soil deposition on a
resistant Finishes fabric either by creating an electric charge that repels the soil or by
producing a smooth surface to which soil will not adhere.
Durability finishes Description
Abrasion-resistant Abrasion-resistant finishes are used on fabrics subject to prolonged
Finish abrasive wear such as pockets, waistband lining, and hatbands.
Slip-resistant Finishes applied to a fabric to reduce or eliminate yarn slippage and
Finishes reduce seam fraying are called antislip, slip-resistant,or nonslip
finishes.
Compressive Used for woven cotton, tubular knit cotton, linen and rayon; the
Shrinkage method consists of mechanically compressing the fabric lengthwise
(Relaxation by overfeeding onto a large roller with damp blankets. Sanforized is a
Method) well known trade mark for fabrics treated by this method.

Durability finishes Description
Heat Set Used for fabrics from thermoplastic fibers such as nylon, polyester
(Relaxation Method) and acrylic; it is based on the principle that thermoplastic
materials will become stabilized in their configuration in which
they happen to be when heated to their softening temperature.
Sponging (Relaxation Used for woolen and worsted fabrics; it consists of thoroughly
Method) wetting the fabric with water or steam and allowing the material
to dry slowly in a relaxed tensionless state.
Resin Treatments Used for fabrics of rayon and cotton; it involves impregnating
(Relaxation Method) rayon and cotton with resins and then curing which stabilizes the
fabric and thus reduces its tendency to distort.

Comfort finishes Description
Antistatic A finish that helps reduce or eliminate static build-up in fabrics.
They are chemical compounds that, when applied to a fabric,
reduces or eliminates the accumulation of static electricity.
Chemical-protective These are finishes that prevent penetration of herbicide or
Finishes pesticide through clothing and prevent easy removal by
laundering of any pesticide on the surface of clothing.
Flame Retardant fabrics treated with these finishes burn in the direct path of flame
Finish but self-extinguish when the source of flame is removed.
Water and Stain They are chemical finishes that resist the penetration of water
Repellent Finishes through the fabric but permit the passage of air or moisture
Waterproof Finishes These are finishes that resist wetting and the penetration of
water.

Environmental finishes Description

Antimicrobial Finish They are applied to fabrics to prevent growth of microorganisms.

Fume Fading Inhibitors Some colours fade, particularly disperse dyes on acetate, caused by
exposure to oxides of nitrogen in the atmosphere. Simple alkaline
substances such as borax are sometimes used as after-treatments, but
they are not permanent.
Metallic and Plastic Metallic and plastic coatings are applied to the back of fabrics.
Coatings Aluminium coatings, modify the warmth and coolness of fabrics, are
used for drapery lining. Plastic coatings help reduce the amount of soil
that penetrates the fabric and delay the passage of heat through the
fabric.
Mothproofing Finish Moth larvae and carpet beetles are known to attack animal-fiber fabrics.
Mothproofing is a chemical that is added to the dyebath during dyeing
of wool fabrics. Treated wool fabrics and silk fabrics are less susceptible
to damage by moths and other insects.

Dyeing, printing & processing defects

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