Content uploaded by Gita Busilienė
Author content
All content in this area was uploaded by Gita Busilienė
Content may be subject to copyright.
297
ISSN 1392–1320 MATERIALS SCIENCE (MEDŽIAGOTYRA). Vol. 17, No. 3. 2011
Pilling Resistance of Knitted Fabrics
Gita BUSILIENĖ
∗
, Kęstutis LEKECKAS, Virginijus URBELIS
Department of Clothing and Polymer Products Tecnology, Kaunas University of Technology,
Studentų 56, LT-51424 Kaunas, Lithuania
Received 02 November 2010; accepted 02 July 2011
Knitted fabrics with different quantity of elastane, conspicuous by high viscosity and elasticity, having one of the
most important performance properties – resistance to pilling are often used in the production of high quality
sportswear. During technological process imitating operating conditions, the behaviour of knitted fabrics may be
changed by different industrial softeners from 12 % to 20 % of active substance, for example fatty acid condensate
(Tubingal 5051) or silicone micro emulsion (Tubingal SMF). The aim of this investigation is to define the influence
of fibrous composition and chemical softeners to the propensity of fuzzing and pilling of plain and plated jersey
pattern knitted fabrics. The results of investigations showed that fibrous composition and thickness of materials
(up to 6 %) and washing as well as softening (from 33 % to 67 %) change the resistance of knitted fabrics to pilling.
Keywords: textile, knitted fabrics, pilling, chemical softening.
INTRODUCTION
∗
Products of knitted fabric are characterized as being
elastic, resilient, soft, they have good draping properties,
and cling well to body to inhibit movement. However,
during exploitation, pills form on the surface of the knitted
fabric, remaining on the surface of the product and
worsening its exterior. The process of formation of pills
consists of three stages [1]: due to mechanical impact to
the surface of rasped products, firstly, the tips of several
fibres of fibre are pulled out creating a fuzzy surface.
Later, broken fibres grip to felt tips and forms separate,
gradually growing pills. Fibres holding these pills are
griped strongly, later however, due to the further
mechanical impact (attrition, washing and other) they may
rub away and fall off.
The resistance of knitted fabrics to pilling depends on
the density of fabric, i.e. when the length of knitted fabric
loop decreases and the surface density increases, the
resistance to pilling grows [2, 3]. When analysing the
influence of weave to propensity of pilling and fuzzing of
knitted fabrics, it was defined that rib knitted fabrics were
resistant to pilling most of all, interlock knitted fabrics are
less resistant, and plain weave knitted fabrics are tend to
pilling more [2
–
6]. It was defined in previous works that
the twist, fuzzing, quantity of fibers, cross-section structure
of knitted fabric change resistance to pilling: when the
twist of yarn is bigger, the fuzzing of fabric then decreases
[7
–
8]. Properly selected formation way of yarn, fabric
weave and facing can improve the quality of knitted fabric
[9]. Washing intensity the process of pilling [10] which
varies depending on chemical softeners used during
washing [11], however, their influence to above-mentioned
process is not fully investigated.
The aim of the work was to define the influence of
fibrous composition and chemical softeners on of fuzzing
and pilling of knitted fabrics.
∗
Corresponding author Tel.: +370-620-88113; fax: +370-37-353989.
E-mail address: gita.busiliene@stud.ktu.lt (G. Busilienė)
MATERIALS AND METHODS
Knitted fabrics of different fibrous composition made
of natural (cotton), artificial (reclaimed bamboo, viscose)
and synthetic (polyester, polyamide) fibre were analysed in
the present work (Table 1). The structure of the
investigated objects was reseached referring the standards
as follows: defining of the fiber content – LST EN ISO
1833; measuring of the density – LST EN ISO
14971:2006; defining of the loop length – LST EN
14970:2006; measuring of the surface density – LST EN
12127:1999; measuring of the thickness – LST EN ISO
5084:2000. The change of the thickness ∆δ was defined
using the thickness gauge SCMIDT DPT 60 DIGITAL, the
precise class 0.01 mm: δ
1
, when p
1
= 1 kPa; δ
2
, when
p
2
= 5 kPa. The surface density and thickness of plain and
plated jersey pattern knitted fabrics chosen for the
investigation are similar, respectively from 202 g/m
2
to
222 g/m
2
and from 0.56 mm to 0.79 mm. Some fabrics
have different quantity of elastane (EL), and this enable to
determine its impact to pilling of knitted fabrics.
To evaluate the influence of washing and chemical
softeners to propensity of fuzzing and pilling of knitted
fabrics, the washing procedure of a specimens
(40 cm × 50 cm) was performed, according to the standard
ISO 6330:2000 [12]. After the washing, specimens were
rinsed in baths with two different softeners: fatty acid
condensate (Tubingal 5051) or silicone micro emulsion
(Tubingal SMF). The composition of washing agent and
softeners as well as the recipe are submitted in Table 2.
The scheme of procedure of knitted fabrics washing and
softening using two different softeners is submitted in
Figure 1.
The propensity to pill and fuzz of dry (control) and
washed as well as softened knitted fabrics was defined
following modified Martindale method (standard ISO
12945-2:2000) [13]. Before the investigation all specimens
were held in standard conditioned conditions
(φ = 65 % ±2 %, T = 20
°C ±2
°C) according to the
requirements of standard ISO 139:2005 [14].
298
Table 1. Characteristics of investigated knitted fabrics
Fabric
symbol Composition Pattern
Density Loop
length,
mm
Surface
density,
g/m2
Thickness
δ1, mm
Thickness
change
∆δ, %
Course dir.
Pc, dm–1
Wale dir.
Pw, dm–1
M1 95 % PES, 5 % EL
Plain and plated jersey
245 150 2.76 202 0.56 -
M2 90 % PES, 10 % EL 250 155 2.88 211 0.63 3.2
M3 87 % PES, 13 % EL 340 200 2.48 219 0.59 3.4
M4 95 % PA, 5 % EL 245 175 2.80 214 0.57 1.8
M5 90 % PA, 10 % EL 205 155 3.10 205 0.70 5.7
M6 95 % Viskose, 5 % EL 215 155 2.83 206 0.79 8.9
M7 92 % Viscose, 8 % EL 230 160 2.81 208 0.62 9.7
M8 88 % Viscose, 12 % EL 310 175 2.62 210 0.59 11.9
M9 95 % Cotton, 5 % EL 265 160 2.75 222 0.77 3.9
M10 95 % Bamboo, 5 % EL 215 170 2.53 215 0.56 3.6
Table 2. Chemical character (structure) and recipe proposals of washing agent and softener‘s
Washing agent/
/softener title Character Chemical character Appearance
Ionic
Character Recipe Proposals
BEICLEAN
RG-N
Low-foaming washing
and emulsifying agent
Modified fatty
alcohol ethoxylates
Colourless
liquid Nonionic ml/kg (dry laundry):
10 ml BEICLEAN RG-N and
5 ml BEIMPLEX NWS (both
mixing approx 30 °C of water),
value pH ~ 7
BEIMPLEX
NWS
Detergency booster for
Professional textile care
Polycarboxylates,
phosphates
Clear, pale
yellow
liquid
Anionic
TUBINGAL 5051
Hydrophylic softener
concentrate, soluble in
cold water
Fatty acid
condensation
product
Light
yellow
liquid
Cationic
ml/l:
120 ml softener/
/880 ml of soft water (approx.
40 °C), value pH = 4.5
TUBINGAL SMF
Softener and additive
for the final finish of
textiles, preferably used
for padding mangle
applications
Functional
polysiloxanes,
micro-emulsified
Transparent,
colourless
liquid
Nonionic
g/l:
1 g of softener/0.,5 g of acetic
acid (100 %) or 3 g of acetic
acid (9 %) (approx 40 °C of
water), value pH = 5.5
During the experiment, using standard photos,
specimens were evaluated after every 1000 rotation cycle
giving the following grades: grade 5 – surface did not
change; 4 – insignificant fuzzing on the surface and (or)
partially formed pills; 3 – medium fuzzing on the surface
and (or) medium pilling. Pills of different size and density
partially cover the surface of specimen; 2 – significant
fuzzing on the surface and (or) significant pilling. Pills of
different size and density cover a large part of the surface
of specimen; 1 – particularly significant fuzzing on the
surface and (or) significant pilling. Pills of different size
and density cover all the surface of specimen.
Fig. 1. Scheme of the knitted fabrics washing and softening procedure
Washed in automatic
washing machine
Washing agent:
BEICLEAN RG-N
and addition
BEIPLEX NWS
Duration: 31 min.
Temperature: 40 °C
Cycle.: 5
Rinsed in a bath
Softener‘s:
TUBINGAL 5051
(fatty acid
condensation product)
TUBINGAL SMF
(functional
polysiloxanes,
micro-emulsified)
Duration: 20 min.
Temperature: 40 °C
Centrifuging
Duration: 10 min.
Spin speed/rpm.: 600
Cycle.: 5
Marking
Drying in horizontal
pozition
Duration: t > 10 h
299
The Martindale abrasion device forces the directing
plate of specimen’s holder to draw the figure of Lissajous.
The movement of Lissajous is changing from the circle till
the gradually narrowing ellipse, and finally becomes line,
from which again the ellipse is formatting obliquely in the
opposite direction up to the picture repeates. The pilling
revolution is considered each rotation, and 16 rotations is
considered as Lissajous figure.
When defining grade 1 of pilling of each fabric
corresponding the number of revolution (P), the
experiment was repeated with two times less the number of
revolutions (TP). This allowed to verification of the results
within the range of insignificant pilling and to prepare
specimens for further investigation.
RESULTS AND DISCUSSION
To define the propensity of fabrics to fuzz and pill, the
results of investigation of control (P and TP) and washed
(Figure 1) knitted fabrics (Table 1) as well as softened in
different softeners (Table 2) were compared.
Knitted fabrics from PES fibres M1 and M2 have the
greatest resistance to fuzzing and pilling: their propensity
to fuzz and pill to grade 1 was not determined even after
14000 revolutions (Figure 2). Knitted fabric M3 (87 %
PES and 13 % EL) is of a very high quality and resistant,
after only 14000 revolutions it was evaluated by grade 1,
while the maximum recommended number of revolutions
in the standard is 7000. Knitted fabrics M1
–
M3 resistance
to propensity of fuzzing and pilling is determined by the
structure of yarn – it is composed influenced by fiber
content [3]: M1 – composed from PES fibers (16.7 tex)
and elastane (2.2 tex), M2 – composed from PES fibers
(16.7 tex, 96 filaments) and elastane (4.4 tex), M3 –
composed from PES fibers (11 tex, 164 filaments) and
elastane (4.4 tex). The exclusiveness of all three fabrics
was also determined by the pattern - plain and plated jersey
pattern. The elastane is inserted into the each line of the
knitted fabric, for other investigated fabrics, into each
second line. Thus, during the pilling investigation of the
fabrics M1 – M3, they scrubbed only the polyester layer,
that‘s on the top, while the lower level, knitted with the
elastane fiber, remained not touched. Therefore elastane
fiber, depending on its quantity in the fabric more or less
pulls, makes a more thick the polyester top layer [5].
Knitted fabrics M4 and M5 are from polyamide fibres,
however their resistance to pilling is different, pilling of
knitted fabric M4 (5 % EL) is evaluated by grade 4 after
the achievement of 14000 revolutions, while fabric M5
(10 % EL) – grade 1 just after 5000 revolutions. Fabric M4
differs from fabric M5 by special method of facing which
changes the resistance of the fabric surface to mechanical
influence. It is suggested, that resistance to the pilling of
the fabrics M4 and M5 differs significantly because of the
fiber content and structure differences: M4 is made from
polyamide 6,6 (7.8 tex from tow fibers) and elastane
(2.2 tex.), and M5 – from polyamide (16.9 tex) and
elastane (4.4 tex). The fabric M5 is more thicker with a
lower density than fabric M4. When sampling during
scrabbling the surface contacts more close to the device top
part. The loops of the fabric M5, characterised by less
density and bigger loop length, are easier going out with
faster fuzzing as well breaking and is less influenced and
less resistance to pilling [2, 3]. The fabric M4 is more
resistant to pilling than M5, because of its pattern, plain
and plated jersey pattern, when elastane is inserted into the
each line of knitted fabric, the elastane fiber is not
scrabbled directly.
The pattern of the fabric M4 is plain and plated jersey
pattern, when elastane is inserted into the each second line
of the knitted fabric.
Knitted fabric M5 from polyamide
fibres is similar to knitted fabrics (M6 and M8) from
viscose fibres by its resistance to pilling because
permissible pilling grade 3 was achieved from 2000 to
3000 of revolutions, and grade 1 – after 5000 revolutions.
Fabric M3 from cotton fibres is of similar resistance to
pilling (grade 3 was achieved after 2000 revolutions),
however it was evaluated by pilling grade 1 after 6000
revolutions.
Tested knitted fabrics
0
1000
2000
3000
4000
5000
6000
7000
8000
9000
10000
11000
12000
13000
14000
15000
M1 M2 M3 M4 M5 M6 M7 M8 M9 M10
Number of revolutions
1
11
1
1
1
1
444
Fig. 2. Investigation (P) results change of knitted fabric propensity to surface fuzzing and to pilling (on five grades of pilling from 5
to 1): – 5; – 5/4; – 4; – 4/3; – 3; –3/2; – 2; – 2/1; – 1
300
0
2
4
6
8
10
12
200 0
400 0
600 0
800 0
100 00
120 00
14000
N
umber of revol
u
tions
Δδ, %
r
= 0.681
M8
M6
M7
M
5
M
9
M
10
M
2
M
3
M
4
M1
0
2
4
6
8
10
12
3
6
9
12
15
Amou nt of e lastane, %
r
= 0. 94 8
r
= 0. 98
4
Δδ, %
PES, EL
VI
,
EL
a b
Fig. 3. Relationship between the change of thickness of knitted fabrics Δδ and number of rotations (a) corresponding maximum pilling
grade and quantity of elastane in fabric (b)
The propensity to fuzz and pill of fabrics M7 (from
viscose fibres) and M10 (from reclaimed bamboo fibres) is
undesirably large: after just 1000 revolutions, specimens
were evaluated by grade 3, and after 3000 revolutions – by
grade 1.
The obtained results showed that the resistance of
fabrics which differ by its main fibrous composition (EL
5 %) to propensity of pilling is different. Specimens of
fabrics from PES and PA fibres were evaluated by grade 4
only after 14000 revolutions, while fabrics from viscose
(M6) and cotton (M9) fibres achieved pilling grade 4 after
just 1000 revolutions. The worst result was in fabrics of
reclaimed bamboo fibres (M10) which achieved pilling
grade 3 after just 1000 revolutions.
The influence of fabric softness to their resistance to
pilling, it was defined that when a change of fabric
thickness increases (Δδ), their resistance to pilling
decreases (Fig. 3, a) [3, 4, 7]. The exception is the results
of investigation of knitted fabrics M9 and M10 which are
determined by fibrous composition of the fabric. The
influence of change of thickness to pilling of fabrics
strongly correlates (r = 0.984) when comparing the results
of knitted fabrics from PES and PA fibres. Strong linear
dependence (r = 0.903) between change of thickness and
resistance to pilling was obtained comparing the results of
fabrics from PES and viscose fibres.
When the quantity of elastane increases in the
composition of knitted fabrics, the change of thickness ∆δ
increases (Fig. 3, b) [5], and the resistance to pilling
decreases (Fig. 2). For example, when the quantity of
elastane of knitted fabrics M1, M2, M3 changes
respectively 5 %, 10 % and 13 %, it changes the thickness
– 0 %, 3.2 % and 3.4 %. First insignificant changes of the
surface of fabric M1 were observed after 6000 rotations
(grade 4), M2 fabric just after 1000 rotations was evaluated
between grade 5 and 4, and evaluated by grade 4 after
3000 rotations. Figure 2 shows how the resistance to
pilling of knitted fabric M3 differs comparing it with M1
and M2. The influence of washing (after 5 cycles) and
softening using two different softeners (fatty acid
condensate and silicone micro emulsion softener) to
propensity of knitted fabrics fuzzing and pilling, it was
defined that the procedure of washing and softening
increases the propensity of knitted fabrics to pilling
(Fig. 4) [10, 11]: the propensity of pilling of M3,
M5 – M10 knitted fabrics increases from 33 % to 67 %.
Washing and processing using chemical softeners do not
have substantial influence to the propensity of pilling of
knitted fabrics M1, M2 and M4.
Subjective pilling evaluation method applied in the
investigation did not allow to define substantial differences
between the results of a specimens influenced by different
Tested knitted fabrics
0
2000
4000
6000
8000
10000
12000
14000
M1 M2 M3 M4 M5 M6 M7 M8 M9 M10
Number of revolution
434 44/3 3 13/2
1
444/3
1
11
1
1
1
1
11
1
1
1
1
1
1
1
1
1
Fig. 4. The results of investigation of maximum propensity of pilling and fuzzing of knitted fabrics (P): – control specimens; –
washed and softened using fatty acid condensate; – washed and softened using silicone micro emulsion softener
301
Tested knitted fabrics
0
1000
2000
3000
4000
5000
6000
7000
M3
M5
M6 M7
M8 M9
M10
Number of revolutions
4/3 4/3
4
3
3 3
4/3
33
3
33
3
3
3
3
3
33/2 3
3
Fig. 5. The results of investigation of permissible propensity of knitted fabrics to fuzz and pill (TP), when the number of cycles is
decreased halfway: – control specimens; – washed and softened using fatty acid condensate; – washed and softened using
silicone micro emulsion softener
softeners. The exception is the results of knitted fabrics
M3, M8 and M9 which showed that specimens softened by
fatty acid condensate are more resistant to pilling than a
specimen softened by silicone micro emulsion softener.
After the performance of additional experiment, when
the number of rotations is twice less than all knitted
fabrics, it was defined that the influence of washing and
softening to pilling of knitted fabrics remains tendentious
(Figure 5). When applying the number of rotations which
was twice less than all investigated fabrics, the lower
evaluation of resistance to pilling is up to grade 3 and it
confirms that fabrics can be exploitable further.
CONCLUSIONS
Knitted fabrics from PES fibres have the greatest
resistance to pilling as their resistance is influenced by
fibre structure and facing. Investigated knitted fabrics from
viscose and reclaimed bamboo fibres have the lowest
resistance to pilling. Knitted fabrics from reclaimed
bamboo fibre distinguished by quickest pilling process:
just after 1000 revolutions it was evaluated by pilling
grade 3. When the change ∆δ of knitted fabric thickness
increases up to 9.7 % the resistance to pilling decreases up
to 64 %. It defined a stronger linear dependence between
the quantity of elastane in investigated knitted fabrics and
thickness change Δδ confirms that the quantity of above-
mentioned fibre has influence to pilling.
The procedure of washing and softening worsened the
resistance to pilling of investigated knitted fabrics from
33 % to 67 %. Fabrics M3, M8 and M9 softened using
fatty acid concentrate are from 25 % to 50 % resistant to
pilling than fabrics softened using silicone micro emulsion
softener. In case of other investigated fabrics, substantial
differences were not defined.
REFERENCES
1. Gintis, G., Mead, E. J. The Mechanism of Pilling Textile
Research Journal 29 1959: pp. 578 – 585.
2. Gykytė, I., Strazdienė, E., Titas, R., Urbelis, V. Pilling of
Knitted Materials Materials Science (Medžiagotyra) ISSN
1392-1320 8 (3) 2002: pp. 316 – 319.
3. Mikučionienė, D. The Influence of Structure Parameters of
Weft Knitted Fabrics on Propensity to Pilling Materials
Science (Medžiagotyra) ISSN 1392-1320 15 (4) 2009:
pp. 335 – 338.
4. Candan, C., Önal, L. Dimensional, Pilling and Abrasion
Properties of Weft Knits Made from Open-End and Ring
Spun Yarns Textile Research Journal 72 (2) 2002:
pp. 164 – 169.
5. Abramavičiūtė, J., Mikučionienė, D., Čiukas, R. Structure
properties of Knits from Natural Yarns and their
Combination with Elastane and Polyamide Threads
Materials Science (Medžiagotyra) ISSN 1392-1320 17 (1)
2011: pp. 43 – 46.
6. Emirhanova, N., Kavusturan, Y. Effects of Knit Structure
on the Dimensional and Physical Properties of Winter
Outerwear Knitted Fabrics Fibres & Textiles in Eastern
Europe 16 (2) 2008: pp. 69 – 74.
7. Uçar, N., Ertuğrul, S. Prediction of Fuzz Fibers on Fabric
by Using Neural Network and Regression Analysis Fibres
& Textiles in Eastern Europe 2 (61) 2007: pp. 58 – 61.
8. Ceken, F. Pilling of Flat Knitted Fabrics Knitting
Technology 2 2000: pp. 16 – 17.
9. Akaydin, M., Can, Y. Pilling Performance and Abrasion
Characteristics of Selected Basic Weft Knitted Fabrics
Fibres & Textiles in Eastern Europe 2 (79) 2010:
pp. 51 – 54.
10. Nergis, B. U., Beceren, Y. Visual Evaluation of the Surface
of Tencel/Cotton Blend Fabrics in Production and Cleaning
Processes Fibres & Textiles in Eastern Europe 3 (68)
2008: pp. 39 – 43.
11. Çelik, N., Değirmenci, Z., Kaynak, H. K. Effect of Nano
Softener on Abrasion and Pilling Resistance and Color
Fastness of Knitted Fabrics Tekstil ve Konfeksiyon 1 2010:
pp. 41 – 47.
12. ISO 6330:2000 Textiles – Domestic Washing and Drying
Procedures for Textile Testing.
13. ISO 12945-2:2000 Textiles – Determination of Fabricc
Propensity to Surface Fuzzing and to Pilling – Part 2:
Modified Martindale method.
14. ISO 139:2005 Textiles – Standart Atmospheres for
Conditioning and Testing.
Presented at the National Conference "Materials Engineering’2010"
(Kaunas, Lithuania, November 19, 2010)
