The effect of different fiber blends in different composition on thermo- physiological comfort properties such as moisture management properties and heat flux or thermal conductivity (qmax) values are assessed. The thermo- physiological comfort properties of developed knitted fabrics (sportswear), composed of 100% polyester, Poly/ Excel, Poly/ Modal in different fiber blends, have been investigated. The moisture management properties are assessed by using the moisture management tester, and the feeling of coldness or warmth is assessed by measuring qmax value on KES-F7 Thermo labo II. Blending polyester fiber with modal & Excel has improved moisture management properties and quick drying rate of the fabrics in comparison to 100% polyester fabric. Peak Heat Flux study (qmax) also indicates that polyester/excel and polyester/modal blend fabrics retain less heat and thus feel cooler as compared to 100% polyester fabric.
There has been enormous market growth for sportswear over the last 20years. Sports Apparel Market was valued at USD 171.25 Billion in 2021, and it is expected to reach USD 287.70 Billion by 2029, exhibiting a CAGR of 6.7% during the forecast period (2022-2029). The sportswear market comprises around 45% of the global sports equipment, sport apparel and footwear market. The sportswear categories account for a sales value of approximately US $265 billion in 2015 as reported in Euromonitor International (2016). Sports apparel, often known as sportswear or activewear, is clothing worn for physical activity or sport. For practical, comfort, or safety reasons, most sports and physical activities necessitate the use of sport-specific apparel. Sport-specific attire includes tracksuits, shorts, T-shirts, and polo shirts. Specialized gear includes swimsuits (for swimming), wet suits (for diving or surfing), ski suits (for skiing), and leotards (for gymnastics). Sports footwear includes trainers, football boots, riding boots, and ice skates. Sportswear is sometimes used as casual fashion apparel. As per the market demand, sportswear can be categorized into four groups, viz performance sportswear, basic sportswear, sports leisurewear, and sports- fashion clothing. Performance sportswear is highly technical- oriented clothing which enhances the performance with special functionality. It is produced in lowest volume and highest price range, whereas basic sportswear is cheaper and more stylish while retaining as many of the material attributes as possible. Sports leisurewear is replica of performance sportswear, worn at home and is sold in higher volume at much smaller price.
In recent years, development in active sportswear fabrics has been progressing to perform high functions and to achieve comfort. Comfort may be defined as a pleasant state of psychological, physiological and physical harmony between a human being and the environment. Wear comfort of active sportswear can be divided into four different aspects, namely Thermo physiological comfort, Sensorial/Tactile comfort, Mobility/Dexterity comfort, psychological comfort [1,2]. Thermo physiological wear comfort concerns the heat and moisture transport properties of clothing and the way it helps the clothing to maintain the heat balance of the body during various levels of activity . The sports and leisure wear exert a barrier for efficient transfer of excess heat resulting in a rise in core body temperature and skin temperature greater than 37°C which increases sweating . Clothing materials should thus have a high moisture retention capacity and high moisture transportation properties to maintain constant temperature
humidity between skin and fabric. This is based on the fact that the
moist fibers can act as a heat reservoir . During sport activity the
human body generates heat quickly due to faster metabolism then
the body’s cooling mechanism attempts to dissipate this extra heat
by producing perspiration. Perspiration should be readily taken
away from the skin to the outer atmosphere before it accumulates
on skin for maintaining cool and dry condition to make the sport
person comfortable and to enhance their performance during
sport activity [6,7].
Moisture management is of critical importance in Active
sportswear fabrics in respect of thermo-physical comfort.
Therefore, it is essential to increase the hydrophilicity of
Polyester. In Moisture management fabrics, the body perspiration
is transported away from the skin to the outer surface of fabric
where it can evaporate quickly in order to accomplishing the
consumer satisfaction of comfort . To achieve such moisture
management, the structural design and quality of fibers are
modified so that the textile products can have good performance
in absorbing, transporting, and dissipating moisture [9,10].
Knitted fabrics are widely used in sportswear due to their
excellent stretch and recovery, porosity, air permeability, softness
and warmth. In last few years knitted fabrics are gaining interest
due to its simple production technique, low cost, high level of
clothing comfort and wide range.11 it also offers good freedom of
movement, shape retention and tailored fit. With the possibility
of numerous combinations of fabric construction and yarns
used, knitted fabric is considered ideal technique for sportswear
development such as t-shirts [11,12].
Polyester (100 den, 150 den Micro PET filament), modal (20s,
24s, 30s, 60s Ne), and excel (20s, 24s, 30s, 60s Ne) were combined
in different proportions for fabric development. Modal and Excel
fibre used in this study were procured from birla Cellulose, Aditya
Birla Group. Polyester filaments used for the study were obtained
from Reliance Industries. Different knitted structured fabric
developed on circular knitting machine such as: Plaiting, single
jersey, pique composed of fibers mentioned above in different
composition were developed at Textile Research & Application
Development Centre (TRADC), Birla Cellulose, Grasim Industries
Ltd. All testing was carried out under environmentally controlled
conditions (21±1°C and 65±2% RH) according to ASTM D 1776.
The moisture management properties of all fabrics were tested
and evaluated by using the Moisture Management Tester (MMT)
according to the AATCC Test Method 195-2009 and feeling of
coldness or warmth was assessed by measuring ‘qmax’ value (peak
heat flux) on KES-F7 Thermo labo II at COE-Sportech Laboratory of
Wool Research Association, Thane. The composition and physical
properties of developed fabrics are presented in table 1.
The sensation of coldness or warmth when skin touches a
fabric is referred to as the “coldness and warmth feeling.” The
feeling of coldness or warmth will vary depending on the amount of
heat transferred from the skin to the fabric. This device measures
that feeling by evaluating the “qmax” value (peak heat flux). Qmax
was measured on KES-F7 (Thermolabo II). The Thermolabo II
consists of (i) a guarded hot plate (BT-Box) with 5cm×5cm area,
(ii) T-box which is essentially a copper plate with a known thermal
capacity insulated on all sides except front face, and (iii) water box
which can be maintained at any temperature by circulating water
Qmax can be measured both with and without constant
temperature base. The present study employed insulated
condition for measuring qmax. The T-box was heated to about 30°C
by keeping it over hot BT-Box. The T-box was then quickly placed
over the fabric, which was kept over a constant temperature of
20°C. The maximum heat flux flowing between the T-Box and the
fabric surface was detected by the electronics of the instrument
. The experiment was carried out in a controlled atmosphere
(65±2% RH and 27±1°C (temp).
The Drying rate tester (AATCC Test Method 201 Drying Rate of
Fabrics: Heated Plate Method) is capable of measuring the rate at
which a textile specimen dries after being exposed to water drying.
The specimen is placed on a heated plate, which is maintained at
37 degrees Celsius to simulate the temperature at which human
skin begins to perspire. Water is dosed on to the heated plate
underneath the specimen to simulate perspiration.
The temperature drops when the specimen is wet and as the
specimen dries, the temperature gradually increases. The machine
software records this change in temperature and automatically
calculates the drying time and rate of the tested specimen. Quick
drying is an important attribute of textiles worn next to the skin,
during sporting activities where the skin is likely to perspire.
Without this characteristic, perspiration does not easily evaporate
from the garment, which can leave a wearer feeling uncomfortable.
Drying rate tester replicates the conditions of use in order to verify
that quick-drying fabrics are performing effectively. This method
is used in the development of quick-drying fabrics and garments
such as base layer garments, football kits, running gear, gym
gear, socks and footwear, and is important in other performance
fabrics such as those used in uniforms for military and emergency
Fabric liquid moisture transport properties in multidimensions,
called moisture management properties significantly influence
human perceptions of moisture sensation. Moisture management
tester (MMT), developed by SDL Atlas to evaluate textile moisture
management properties, was used. This method can be used to
quantitatively measure liquid moisture transfer in one step in a
fabric in multiple directions. Moisture spreads on both surfaces
of the fabric and transfers from one surface to the opposite. Here,
ten indices are introduced to characterize the liquid moisture
management properties of fabric. Electrical conductivity changes
are measured as the test solution migrates across the top of, though
and across the bottom of the test specimen. Factors affecting this
movement include fabric water repellency, water resistance, and
water absorption, along with the fiber and yarn wicking properties.
Perspiration is mimicked with TM 195. The results obtained with
this test method are based on water resistance, water repellency
and water absorption characteristics of the fabric structure,
including the fabrics’ geometric and internal structure and the
wicking characteristics of its fibers and yarns .
Ten indices of the MMT, used to characterize the moisture
management properties of a fabric, are as mentioned below:
(i) Wetting time top (WTt)
(ii) Wetting time bottom (WTb)
(iii) Top absorption rate (MARt)
(iv) Bottom absorption rate (MARb)
(v) Top maximum wetted radius (MWRt)
(vi) Bottom maximum wetted radius (MWRb)
(vii) Top spreading speed (SSt)
(viii) Bottom spreading speed (SSb)
(ix) Accumulative one-way transport capacity (OWTC)
(x) Overall moisture management capability (OMMC)
The OWTC is the difference in accumulative moisture content
between the two surfaces of the fabric. The OWTC reflects the oneway
liquid transport capacity from the top (inner) surface to the
bottom (outer) surface of the fabric . The OMMC is an index
indicating the overall capacity of the fabric to manage the transport
of liquid moisture, which includes following three aspects:
(i) Average moisture absorption rate at the bottom surface
(ii) One-way liquid transport capacity
(iii) Maximum moisture spreading speed on the bottom
According to AATCC Test Method 195-2009, the indices are
graded and converted from value to grade based on a five-grade
scale (1-5): 1–poor, 2–fair, 3– good, 4–very good and 5– excellent.
Table 2 shows the range of values converted into grades.
qmax is the feeling of coolness or warmth. It means the feeling
we get when human skin touches an object. It is measured as
the maximum amount of heat flow between the body and the fabric
(Watt/m2). The higher the value, the cooler we feel.
Figure 1 indicates qmax values for the fabric’s samples. Table
3 indicates qmax values for eight fabrics under study. The result
obtained indicates that Pique Structure of Polyester blended with
Excel in blend ratio of 73/27 gives the lowest value of qmax out of all
08 fabrics developed which corresponding that that less amount
of heat transferred from the skin to the fabric compare to other
fabrics. In the case of Plaiting Structure of Polyester blended with
Excel and Modal, blend ratio of 56/44 Poly/Excel gives the highest
value of qmax which corresponding that that less amount of heat
transferred from the skin to the fabric compared to other fabrics.
Polyester/Modal 60/40 give highest qmax values in single jersey
knitted structure which is 0.251 watt/cm2 .
Figure 2 indicates the drying rate of the developed fabrics
samples. Table 3 indicates that Poly/ Modal fabric blend ratio -
56/44, Poly/ Excel fabric blend ratio - 56/44 and Polyester/Excel
fabric blend ratio 70/30 are having lesser drying time (sec) and
better drying rate (ml/hr) among the others. Thus, these fabrics
can be considered as quick dry fabrics. Plaiting Structure of
Polyester blended with Modal & Excel, the blend ratio of 75/25
polyester with Modal fibers gives lowest drying rate among all
developed fabrics. Among the developed single jersey knitted
structures of Polyester blended with Modal & Excel fibers,
Polyester/Excel 70/30 gives the highest value of drying rate. In
case of Pique Structure of Polyester blended with Excel in blend
ratio of 73/27, the Drying rate found to be equal to Polyester/
Modal 60/40 blend ratio in single jersey structure.
Table 3 indicates that all the eight developed fabrics have good
to excellent overall moisture management capability and qualifies
to call as moisture management fabrics & table 4 indicates the test
results of moisture management fabrics. Figure 3 indicates the
overall moisture management capability of fabrics.
Comparison between single jersey structures of Polyester
blended with Modal & Excel demonstrates that blending polyester
with such fiber improved OMMC significantly in 70/30 blend
ratio of polyester with either Modal or Excel fibers. This indicates
that blending modal or excel fibers with polyester makes it more
suitable for sportswear application without using any hydrophilic
chemical finishes. In case of Plaiting Structure of Polyester blended
with Modal & Excel, the blend ratio of 75/25 polyester with Modal
fibers gives higher Overall Moisture Management Capability while
blend ratio of polyester with either Modal or excel fibers in the
proportion of 56/44 gives lower OMMC values. In the case of
Pique Structure of Polyester blended with Excel in blend ratio of
73/27, the OMMC values were found to be increased.
Polyester has outstanding dimensional stability and excellence
resistance to dirt, alkalies, mold and most of the organic solvent and
also has excellent heat resistance but is essentially hydrophobic
fiber and does not absorb moisture therefore Polyester to be
used in sportswear need to be treated with chemicals to increase
its moisture management properties. Polyester has high initial
wetting time and low spreading speed therefore it can be used
effectively as a base fabric in two layer sportswear where it can
transfer moisture quickly to outer hydrophilic layer. Out of 08
fabrics selected in the present study, Polyester/ Excel in the
blend ratio of 56/44 among plaiting structure fabrics gives a
higher Drying rate & higher Peak heat flux (qmax) value i.e., more
coolness and also gives good moisture management. Polyester/
Excel in the blend ratio of 70/30 also gives higher Drying rate &
Good Peak heat flux (qmax) value i.e., more coolness and also gives
excellent moisture management among single jersey structure and
may be suitable blend composition for designing in sportswear
application. Therefore, Polyester if blended with Excel can be used
effectively for sportswear applications.
The authors of this article are thankful to the Management of
Wool Research Association & Institute of Chemical Technology for
their continuous support, valuable guidance & input. The authors
gratefully acknowledge the R & D Project support received from
Ministry of Textiles, Govt. of India & Textile Research & Application
Development Centre (TRADC), Birla Cellulose, India.