PILLING
Pilling
Pilling is the formation of little balls of fibers (pills) on the surface of a fabric which is caused by
abrasion in wear.
Pilling is the tendency of fibers to come loose from a fabric surface and form fibre balls.
The degree of pilling will depend on the type of yarn or fabric, the structure and finish.
Some yarns are very sensitive to pilling through friction, even rubbing the yarn back and forth a few
times.
The softer the yarn (e.g. brushed alpaca); there will be more tendencies to pill.
Causes of Pilling:
Pilling was found in the knitted woollen goods that were made from soft twisted yarns.
With the introduction of man-made fibres the problem has been aggravated. The causes
of the pilling are:
Formation of fibre fuzz on the fabric surface due to abrasion.
Due to rubbing action on fabric.
For using fibres that have greater breaking strength and lower bending stiffness.
Soft twisted yarn and loose fabric structure (e.g., knit fabric) have a rapid fibre
pull-out rate.
Due to excess short fibres the amount of protruding fibres will increase.
For using yarn with increased hairiness value.
Due to migration of fibres from constituent yarn in fabric.
Fabrics that are made from blended fibres shown a greater pilling tendency.
Reduction of pilling
Pills are formed as the fibres come out from the yarns in the fabric. The amount of pilling can be
reduced if the yarns can hold the fibres more firmly. Some of the measures that can be taken to
reduce the pilling rate are given below:
By increasing twist in yarn.
By using longer fibres during yarn production.
By brushing and cropping of the fabric surface to remove loose fibre ends.
By reducing yarn hairiness,
By using special chemical treatment to reduce the fibre migration.
By increasing inter-fibre friction.
By using fibres of greater linear density.
By using a high number of threads per unit length during fabric manufacturing.
Martindale Pilling Test Pilling Box Test Random Tumble Pilling Test
ICI Pilling Box Test
Four specimens each 5 inches ×5 inches (125 mm ×125 mm) are cut from the fabric.
A seam allowance of 12mm is marked on the back of each square. In two of the
samples the seam is marked parallel to the warp direction and in the other two parallel
to the weft direction.
The samples are then folded face to face and a seam is sewn on the marked line.
Figure: Preparation of a Pilling Sample
This gives two specimens with the seam parallel to the warp
and two with the seam parallel to the weft.
Each specimen is turned inside out and 6mm cut off each end of
it thus removing any sewing distortion.
The fabric tubes made are then mounted on rubber tubes so that
the length of tube showing at each end is the same. Each of the
loose ends is taped with poly vinyl chloride (PVC) tape so that
6 mm of the rubber tube is left exposed as shown in Figure.
All four specimens are then placed in one pilling box.
The samples are then tumbled together in a cork-lined box as
shown in Figure.
The usual number of revolutions used in the test is 18,000
which take 5 hrs.
Figure: Pilling Box
Assessment with Standard Photographs
The specimens are removed from the tubes and viewed using oblique lighting. The samples
are then given a rating of between 1 and 5 with the help of Standard photographs or the
descriptions in the Table.
Rating Description Considered Points
5 No change No visual change
4 Slight change Slight surface fuzzing
The specimen may exhibit one or both of the
following:
3 Moderate change
a) Moderate fuzzing
b) Isolated fully formed pills
2 Significant change Distinct fuzzing and/ or pilling
Dense fuzzing and/or pilling which covers
1 Severe change
the specimen
Martindale Abrasion & Pilling Tester
Pilling tests can be performed with a standard Martindale abrasion tester. Some modifications need to be
carried out for this. In most of cases, the tested fabric is set both in the holder and on the baseplate. In this way
fabric is rubbed against itself. Bare spindle (without added weight) is used in most of the methods. The fabric
that is set in the holder is assessed usually. The result is assessed against a set of photographic standards. This
method is faster than the ICI Pilling Box Test. Different manufacturing companies like James Heal, Testex,
SDL Atlas, etc., has their own versions of Martindale abrasion and pilling tester. Here, a Martindale tester
model of James Heal is discussed.
Brand: James Heal
Model: 1605 Midi- Martindale
Number of stations: 5
Woven and knitted fabrics from staple fibre yarns are tested for
measuring the pilling tendency of them in this instrument.
Specimens are rubbed against each other or abrasive cloth. The
degree of pilling is assessed by comparing with the photographs
of standard fabrics with a written descriptive table.
Machine Parts
Loading Weight on Spindle
Abrading Tables
Finger Grips (to aid in Lifting Top Plate
Clamp Rings
Support Towers for Top Plate
Touch Screen (User Interface)
Sample Holder
Rubbing Motion
The instrument has three distinct path for rubbing action.
Rubbing Action Motion Type
A Straight Line
B 24 mm Lissajous
C 60.5 mm Lissajous
Difference between Abrasion and Pilling Test in Martindale Tester
Operation Mode Abrasion Pilling
Standard EN ISO 12947 EN ISO 12945-2
Exposed area of test specimen 6.45 𝑐𝑚2 64.5 𝑐𝑚2
9 kPa (for apparel) 2.5 cN/ 𝑐𝑚2 (for knit)
Working Pressure on test Specimen
12 kPa (for upholstery) 6.5 cN/ 𝑐𝑚2 (for woven)
Rotational Speed 47.5 ± 2.5 rpm
Total Stroke 60.5 ± 0.5 mm 24 ± 0.5 mm
Sample Cutter Diameter 38 mm 140 mm
