Denim is no more “work wear’’ in the present era. More than a need, it is a fashion commodity for every age group, specifically for youth. Garments with multiple permutations and combinations of denim fabric variables like fibers, yarns, and Lycra % and weaving techniques are available with differing garment design statements, but the comfort aspect is slightly ignored. To cater for the masses living in hot and humid areas, a denim fabric is being projected with varying garment constructional parameters. Regenerated cellulose-based fibers/yarns are considered as ecofriendly, cool, soft, fairly strong, and durable among other man-made and natural fiber-based yarns. The present study is an attempt to develop comfortable denim clothing using regenerated cellulose fiber derivatives, maintaining its traditional rustic look for tropical regions. Fabric performance evaluation methods were used to ascertain the performance of the newly developed clothing.
Denim has now clearly established itself as the definitive “street wear” fabric and has wide age and socioeconomic appeal. Denim mills are now, more than at any time previously, spending large amounts of money in developing new concepts in denim, which in turn means that all jeans manufacturers will experiment with and achieve new levels of finishing [
In this research work, different fabric is developed with using regenerated cellulose and its derivatives like modal, Tencel, and bamboo yarns in weft way of the fabric to impart cool sensation. Viscose filament was also used to give lustrous look to fabric and to make product comfortable and trendier. All yarns used were ring yarns with 2/30 s count in both warp and weft direction. All fabric samples with 3/1 twill weave were prepared in GBTL (Grasim Birla Textile Ltd.) Fabric Mills, Bhiwani (Haryana), and these samples were processed in their processing unit and were subjected to scouring at 60°C–70°C with DTC soap in jigger machine and dried in Stenter at 160°C. Different fiber, yarn, fabric, and machine parameters are stated in Tables
Specifications of fibers.
S. number | Fiber type | Fiber |
Fiber fineness |
Specific |
Dry tenacity |
Wet tenacity |
Cross-sectional shape | Elongation at |
Moisture |
---|---|---|---|---|---|---|---|---|---|
1 | Cotton | 29.08 | 4.3 | 1.52 | 2.1 | 3.88 | Bean | 6.1 | 7 |
2 | Viscose | 29 | 4 | 1.53 | 2.7 | 1.46 | Bean | 6 | 7 |
3 | Viscose filament | 51 | 4.23 | 1.52 | 2.6 | 1.48 | Serrated | 20 | 11.5 |
4 | Bamboo | 37.5 | 4.75 | 1.52 | 2.6 | 1.819 | Serrated | 21 | 11.5 |
5 | Modal | 38 | 3.96 | 1.32 | 2.33 | 2.67 | Filled with microholes & gaps | 23.8 | 13.03 |
6 | Tencel | 38 | 3.38 | 1.50 | 3.8 | 4.245 | Round | 16 | 12 |
Yarn and fabric parameters.
Sample code | Fabric type | Yarn count | Strength |
Modulus |
Coefficient of friction |
Hairiness |
GSM of fabric |
Fabric thickness |
---|---|---|---|---|---|---|---|---|
A | Indigo dyed cotton × grey cotton | 2/30 s | 19.23 | 234 | 0.25 | 11.18 | 246 | 0.62 |
B | Indigo dyed cotton × viscose | 2/30 s | 28.62 | 264 | 0.25 | 10.315 | 257 | 0.59 |
C | Indigo dyed cotton × viscose filament | 286 D | 20.55 | 394 | 0.245 | 0 | 230 | 0.46 |
D | Indigo dyed cotton × bamboo | 2/30 s | 18.01 | 182.8 | 0.275 | 4.74 | 262 | 0.645 |
E | Indigo dyed cotton × modal | 2/30 s | 29.9 | 404.1 | 0.23 | 8.2 | 252 | 0.54 |
F | Indigo dyed cotton × Tencel | 2/30 s | 29.9 | 362.7 | 0.28 | 5.855 | 250 | 13.65 |
All usual tests for yarn and fabrics were done like linear density (yarn and fabric), strength (yarn and fabric), flexural rigidity, air permeability, MVTR, and so forth. Some specific tests were carried out to check cool and comfortable sensation of the fabric. These are described as below.
Alambeta, a test instrument, has been developed at the Technical University of Liberec in Czech Republic for assessing thermal absorptivity of textile fabrics. It is computer-controlled. It calculates the thermal absorptivity (Ws1/2/m2K) by using the statistical parameters of measurements for thermophysiological properties like thermal conductivity, thermal resistance, maximum level of heat flux, and sample thickness.
The first sensation experienced by a human being while touching a fabric is a “warm-cool’’ feeling as a result of heat exchange that takes place, owing to the temperature difference between the fabric surface and the human skin [
Textest FX 3300 instrument was used to measure air permeability of the samples (cm3/cm2/S−1) via standard TS 391 EN ISO 9237 method. The measurements were performed at a constant pressure drop of 98 Pa (20 cm2) test area [
The Grace, Cryovac Division, has developed a Moisture Vapour Transmission Cell (MVTR Cell), which offers a faster and more simplified method for measuring the water vapour transmission behavior of a fabric. In principle, the cell measures the humidity generated under controlled conditions as a function of time [
The fabric samples were tested at the Indian Institute of Technology, Delhi, India. The tensile and shear properties were studied on KES-FB1 (tensile and shear tester). The tensile properties were measured by plotting the force extension curve between zero and a maximum force used of 500 gf/cm and the recovery curve. Shear properties were measured by shearing a fabric sample parallel to its long axis, by keeping a constant tension of 10 gf/cm on the clamp. Bending properties were measured on KES-FB2 (pure bending tester) by bending the fabric sample between the curvatures −2.5 and 2.5 cm−1.
KES-FB3 (compression tester) was used to calculate compression properties, by placing the sample between plates and increasing the pressure while continuously monitoring the sample thickness to a maximum pressure of 50 gf/cm2. the total hand values were calculated from the sixteen mechanical properties using the prescribed procedure by Kawabata and Niwa, as shown in Figure
As all fibers were cellulose-based, ANOVA analysis was used to identify the statistically significant difference (
Thermophysiological properties include thermal absorptivity, thermal resistance, and heat conductivity. A warm/cool feeling is the first sensation; when a human touches a garment that has a different temperature than the skin, heat exchange occurs between the hand and the fabric [
Thermophysiological properties.
Fabric code | Thermal absorptivity (Ws1/2/m2K) | Heat conductivity (W/mK) | Heat resistance (m2K/W) |
|
---|---|---|---|---|
A | 98.671 | 29.41 | 21.17 | 0.343 |
B | 102.2 | 28.31 | 21 | 0.358 |
C | 106.32 | 25.97 | 17.87 | 0.373 |
D | 99.2 | 29.78 | 21.67 | 0.34 |
E | 107.91 | 28.52 | 19 | 0.372 |
F | 88.67 | 27.18 | 20.85 | 0.334 |
It was observed that the other types of fabrics gave in between values of maximum level of contact heat flux.
Air permeability indicates ability of the fabric to allow atmospheric air to be in contact with user skin and passage of water vapour (perspiration) to move out into the atmosphere. Sample A gave the lowest value among all, which may be due to more yarn hairiness and cover factor. The more the cover factor is, the lesser the air permeability will be and vice versa. The comfort or cool feel of the fabric will increase by increase in air-permeability value. It was found that the highest value is in case of sample C among all due to its high fiber fineness and less hairiness and provides the best cool feel as compared to other fabrics.
EMT has a good correlation with fabric handle. So, the higher the extensibility, the better the fabric quality from the handle point of view. A high EM value also indicates greater wearing comfort. Tensile linearity signifies the uniformity in tensile load-bearing capacity [
Bending rigidity is a measure of ease with which fabric bends. Bending rigidity of fabric depends on the bending rigidity of constituent fiber and yarns from which the fabric is manufactured.
The shear rigidity of a fabric depends on the mobility of cross threads at the intersection point, which depends on the weave, yarn diameter, and the surface characteristics of both fiber and yarn. In comparative graphs of bending rigidity and shear rigidity of different samples, as shown in Figures
The handle, comfort, and aesthetic properties of the cloth are influenced by the surface characteristics of fabric, yarn, and fiber. SEM of fiber surface morphology is shown in Figures
Cross-sectional/longitudinal view of cotton.
Cross-sectional/longitudinal view of viscose.
Cross-sectional/longitudinal view of bamboo fiber.
KES-F graphs for bending of different fabric samples.
KES-F graphs for shear property.
KES-F graphs for surface characteristics.
KES-F graphs for compression property.
Compressibility contributes to a feeling of bulkiness and spongy property in the fabric. The compressibility of a fabric mainly depends on yarn packing density and yarn spacing in the fabric. During fabric compression, initially the protruding fibers get compressed in the fabric surface, secondly the yarn gets compressed by the movement of constituent fibers, and finally the fiber gets compressed and its cross-sectional shape changed. Higher value of linearity in compression is the indication of hard feeling in material. Sample B has exhibited slightly higher WC which may be attributed due to the lower packing density and higher hairiness than bamboo and viscose yarn. Compressibility also relates with primary hand values (Fukurami and fullness) of the fabric. The reason for higher value of compressional energy in case of sample B was due to the noncircular cross-sectional shape (Figure
Koshi represents stiffness of the fabric and contributes 30% among all PHV towards coolness of the fabric. Shari represents crispness of the fabric. The higher the value of shari is, the cooler the fabric will be. Shari contributes 35% among THV of the fabric. Here again sample C shows the highest shari value among all. Hari represents the fabric hardness, boardiness, and antidrape stiffness of fabric. Cotton × bamboo fabric was given the lowest value of hari, that is, 7.91. Hari is 10% contributor towards cool feel of the fabric. So, sample C showed more cool sensation.
Mean values of men’s summer suiting.
S. number | Fabric type | Koshi | Shari | Fukurami | Hari |
---|---|---|---|---|---|
1 | A | 7.30 | 2.58 | 8.38 | 8.26 |
2 | B | 6.96 | 2.94 | 8.58 | 8.25 |
3 | C | 8.41 | 5.28 | 7.94 | 9.10 |
4 | D | 6.68 | 1.92 | 8.65 | 7.91 |
5 | E | 7.28 | 2 | 8.54 | 8.81 |
6 | F | 6.81 | 2.51 | 8.75 | 8.16 |
Primary hand values.
S. number | Property | Unit | A | B | C | D | E | F |
---|---|---|---|---|---|---|---|---|
1 | Extensibility ( |
% | 5.515 | 5.735 | 4.695 | 5.135 | 4.710 | 5.455 |
2 | Linearity of load-extension curve ( |
— | 0.712 | 0.655 | 0.780 | 0.676 | 0.720 | 0.657 |
3 | Tensile energy ( |
gf⋅cm/cm2 | 0.825 | 9.400 | 8.975 | 8.675 | 0.475 | 8.950 |
4 | Tensile resilience ( |
% | 54.100 | 52.390 | 65.975 | 52.450 | 47.790 | 55.890 |
5 | Bending rigidity ( |
gf⋅cm2/cm | 0.172 | 0.144 | 0.227 | 0.147 | 0.207 | 0.148 |
6 | Hysteresis of bending moment (2 |
gf⋅cm/cm | 0.139 | 0.142 | 0.105 | 0.141 | 0.214 | 0.159 |
7 | Shear stiffness ( |
gf/cm/degree | 2.180 | 1.538 | 3.398 | 1.613 | 1.538 | 1.500 |
8 | Hysteresis of shear force at 0.5 deg of shear angle (2 |
gf/cm | 5.012 | 3.575 | 4.975 | 3.513 | 3.575 | 3.425 |
9 | Hysteresis of shear force at 5 deg of shear angle (2 |
gf/cm | 7.412 | 5.938 | 7.400 | 6.412 | 5.938 | 5.763 |
10 | Coefficient of friction ( |
— | 1.765 | 1.582 | 1.773 | 1.788 | 1.665 | 1.688 |
11 | Mean deviation of |
— | 0.715 | 3.992 | 0.948 | 0.715 | 0.887 | 1.070 |
12 | Geometrical roughness ( |
|
3.673 | 6.493 | 2.177 | 3.462 | 3.103 | 3.618 |
13 | Linearity of compression ( |
— | 0.336 | 0.306 | 0.269 | 0.255 | 0.290 | 0.295 |
14 | Compression energy ( |
gf⋅cm/cm2 | 0.412 | 0.293 | 0.233 | 0.307 | 0.260 | 0.277 |
15 | Compression resilience ( |
% | 31.247 | 33.273 | 34.810 | 29.483 | 36.233 | 33.943 |
16 | Thickness ( |
mm | 1.066 | 1.188 | 0.801 | 1.040 | 0.887 | 0.973 |
17 | Weight ( |
mg/cm2 | 104 | 109.32 | 93.89 | 107.77 | 104 | 104.89 |
This research shows that cellulosic derivatives like modal, bamboo, and Tencel yarns have different properties due to their manufacturing techniques and raw material, but no significant effect on end product. Cellulosic content determines the moisture % within the fiber, resulting in cooling sensation while touching to the human body. Decrease in yarn fineness and hairiness will improve the clothing comfort by providing more area of conduct of fabric to the wearer. Smooth and soft surfaced fabrics will add on soothing sensation to clothing for tropical regions. Thermophysiological properties depend upon ability to conduct heat and contact area of fabric with the body; therefore in case of filament fabric it is showing most favorable values. Air permeability is a measure of passage of air through the fabric that implies comfort of the clothing with less cover factor.
Kawabata evaluation is helpful to determine comfort behavior of fabrics by objective evaluation by doing tensile, bending, shear, compression, and surface properties evaluation. The cumulative results will give PHV (primary hand values) and THV (total hand values). PHV like koshi, shari, and hari were highest in case of sample C. Samples E, A, B, F, and D were showing gradually decreasing PHV. Fukurami shows fullness, bulkiness of fabrics which is highest in case of samples D and B. Hence, samples C and F showed the largest value and contributing towards the comfortability in summer suiting.
The authors declare that there are no competing interests regarding the publication of this paper.