Dimensional,physical and thermal comfort properties of plain knitted fabrics made from modal viscose yarns having microfibers and conventional fibers

The dimensional, some physical and thermal comfort properties of the plain knitted fabrics having modal viscose microfibers in three different stitch lengths are investigated in comparison with the similar fabrics having conventional modal viscose fibers. The fabrics made from microfibers and conventional fibers exhibit different dimensional properties. The stitch density results and the dimensional constants calculated at the fully relaxed state reveal that the fabrics with microfibers tend to have lower shrinkage tendency than those with conventional fibers. The statistical results show that the fiber type (or fiber fineness) and the stitch length affect the some physical properties and all of the thermal comfort properties of the fabrics significantly. The bursting strength values of the fabrics with microfibers are observed to be slightly higher than those of the fabrics with conventional fibers. However, the difference between the bursting strength values of these fabrics is found to be statistically unimportant. The fabrics with microfibers reveal lower thickness and air permeability and, higher pilling tendency than those with conventional fibers. It is also observed from the thermal comfort results that the fabrics made from microfibers have higher thermal conductivity, thermal absorptivity and maximum heat flux values and, lower thermal resistance and thermal diffusivity values. Because of the higher thermal absorptivity and maximum heat flux values, the fabrics from microfibers provide cooler feeling when compared with those from conventional fibers.     

Comparative study on the characteristics of knitted fabrics made of vortex-spun viscose yarns

Murata vortex spinning system is based on the air jet spinning system. The vast majority of previous works deal with the properties of vortex spun (VS) yarn and the spinning system. In this study, we investigated knitted fabrics from VS yarn in comparison with fabrics from ring (RS), compact (CS) and open-end rotor (OES) spun yarns made from viscose. The effect of yarn spinning system on dimensional and physical properties of knitted fabrics was explained with specific attention to fabrics from VS yarn. Shrinkage of fabrics from VS yarn has the lowest at widthwise direction, while having the highest at lengthwise direction. It is shown that the order of fabric spirality and twist liveliness for yarns from different spinning systems are quite similar. However, relation between loop shape factor and angle of spirality is inconsistent. Angle of spirality of fabrics from VS yarn is higher than fabrics from OES yarn, but lower than that of others. The bursting strength of fabrics from VS yarn is lower than that of those from RS and CS yarns and higher than that of those from OES yarn. From this study, it is also evident that fabrics from VS yarn have the lowest pilling tendency and highest resistance to abrasion.     

A comparative study of cotton knitted fabrics and garments produced by the modified low twist and conventional ring yarns

Spirality is one of the major potential problems in knitted fabrics and garments. It affects the aesthetics and physical properties of the garment produced, such as the seam displacement, shape retention, pattern distortion and sewing difficulties. In this paper, a comparative study has been carried out to evaluate the physical performance of 100 % cotton knitted fabrics and garments produced by the modified low twist and conventional ring yarns through the actual wearing and washing trials. Experimental results showed that the properties of side seam displacement, fabric spirality, dimensional stability and skewness change of the T-shirts and sweaters made by the modified single yarns are comparable to those of garments made from the control plied yarns but much improved when compared to those from the control single yarns. In addition, the pilling resistance and bursting strength of the knitted fabrics made by the modified single yarns can still maintain a reasonably high level at a low yarn twist.     

A comparative study of finer conventional and modified cotton yarns and their resultant woven fabrics

A modified ring spinning technique has been recently developed by incorporating false twisting devices into the conventional ring frame. Its application on the coarser yarn counts (7–32 Ne) showed notable advantages in modified yarn and fabric performance. More recently, it was noted that this technique can also be applied for producing finer cotton yarns. Thus this paper aims to carry out a systematic study of the physical properties of the finer modified yarns (80 Ne) and woven fabrics with respect to the conventional ones. Physical properties of conventional and modified single yarns were evaluated and compared. These two types of single yarn were used for the production of woven fabrics. Moreover, the above two types of single yarn were also plied and used for the production of woven fabrics under a commercial condition. All woven fabrics were assessed in terms of fabric tensile strength, tearing strength, abrasion resistance, fabric weight, and air-permeability as well as other fabric performance measured by the Kawabata Evaluation System (KES). Experimental results showed that finer modified yarns and fabrics exhibit higher strength, lower hairiness, and improved abrasion resistance, slightly better compression property, and smoother surface with relatively larger thickness.     

Dimensional and physical properties of plain knitted fabrics made from 50/50 bamboo/cotton blended yarns

In this study, the dimensional and some physical properties of plain knitted fabrics made from 50/50 bamboo/cotton blended yarns are investigated. In order to see the differences and similarities, the results are then compared with those for similar fabrics knitted from 50/50 conventional viscose/cotton and 50/50 modal/cotton blended yarns. Each fabric type was produced with three different stitch lengths. After all fabrics were dyed under identical dyeing conditions, they were subjected to dry and full relaxation treatments. For dimensional properties of fabrics, course, wale and stitch densities were measured. Then, by calculating statistically best-fit lines passing both through the experimental points and the origin, dimensional constants i.e. k values were predicted in terms of the fiber types. The result show that each fabric type knitted from bamboo/cotton, viscose/cotton and modal/cotton blended yarns behaves in a similar manner. However, in both dry and fully relaxed states, the modal/cotton knitted fabrics tend to have slightly higher k values than the bamboo/cotton and viscose/cotton knitted fabrics. For physical properties, fabric weight per unit area, thickness, bursting strength, air permeability and pilling were evaluated. The results show that the weight, thickness and air permeability values are independent of the fiber type. Plain knitted fabrics from modal/cotton blended yarns have the highest bursting strength values. Plain knitted fabrics from bamboo/cotton blended yarns tend to pill less.     

Color and whiteness properties of fabrics knitted from different hybrid core-spun yarns containing metal wire

In this study, the color and whiteness properties of fabrics knitted from ring, siro and compact core-spun yarns containing metal wire were investigated. In general, an increase in the metal ratio of yarns causes a decrease in the whiteness and color strengths of fabrics. In our study, spinning method had no statistically significant effect on either the T _w or K/S values of fabrics while the effect of spinning method on the whiteness index of fabrics was briefly observed. Fabrics knitted from siro spun yarns showed higher whiteness properties than those of fabrics knitted from compact and ring spun yarns. This might be explained by the superior covering effectiveness of the siro spinning method on metal wire.     

Comfort characteristics of fabrics made of compact yarns

Comfort is one of the most important aspects of clothing. Thermal comfort is related to fabric’s ability to maintain skin temperature and allow transfer of perspiration produced from the body. Properties like thermal resistance, air permeability, water vapor permeability, and liquid water permeability are suggested as critical for thermal comfort of clothed body. In this study the fabrics developed from the EliTe compact yarns are compared with the fabrics made from normal yarns. The thickness of the fabrics made from EliTe® compact yarns is also slightly less than the fabrics made from normal yarns. Fabrics made from EliTe® compact yarns have shown greater air permeability as compared to the fabrics made from normal yarns. It is observed that, thermal resistivity values of the fabrics developed from EliTe® compact yarns are lower than the fabrics made from normal yarns indicating they are cooler fabrics compared to normal fabrics. Fabrics developed from the EliTe® compact yarns have shown slightly higher values of MVTR (moisture vapor transmission rate) as compared to the fabrics made from the normal yarns. The wicking characteristic of fabrics developed from EliTe® compact yarns was slightly higher than the fabrics developed from normal yarns.     

Compression properties of weft knitted fabrics consisting of shrinkable and non-shrinkable acrylic fibers

High-bulk worsted yarns with different shrinkable and non-shrinkable acrylic fibers blend ratios are produced and then single jersey weft knitted fabrics with three different structures and loop lengths are constructed. The physical properties of produced yarns and compression properties of produced fabrics at eight pressure values (50, 100, 200, 500, 1000, 1500 and 2000 g/cm²) were measured using a conventional fabric thickness tester. Then, weft-knitted fabric compression behavior was analyzed using a two parameters model. It is found that at 40% shrinkable fibre blending ratio the maximum yarn bulk, shrinkage, abrasion resistance and minimum yarn strength are obtained. It is also shown that high-bulk acrylic yarn has the highest elongation at 20% shrinkable fibre blend ratio. The statistical regression analysis revealed that the compression behavior of acrylic weft-knitted fabrics is highly closed to two parameter model proposed for woven fabrics. It is also shown that for weft-knitted structure, there is an incompressible layer (V′) which resists against high compression load. Acrylic weft-knitted fabrics with knit-tuck structure exhibit higher compression rigidity and lower softness than the plain and knitmiss structures. In addition, at 20% shrinkable fibre blend ratio, the high-bulk acrylic weft-knitted fabrics are highly compressible.     

Mechanical properties of composites made from locally manufactured carbon fabrics and the composites produced from air-textured glass yarns

Composite materials have a wide range of applications in structural components because of their high strength-to-weight and stiffness-to-weight ratios. However, the most crucial and common life-restricting crack growth mode in laminated composites i.e. delamination is of great concern. Air jet texturing was selected to provide a small amount of bulk to the glass yarn. The purpose was to provide more surface contact between the fibres and resin and also to increase the adhesion between the neighbouring layers. These were expected to enhance the resistance to delamination in the woven glass composites. The development and characterisation of core-and-effect textured glass yarns was presented in the previous paper. This paper describes the comparison of the mechanical properties of composites produced from air-textured glass yarns and the composites made from locally manufactured carbon fabrics. The tensile, flexure and inter-laminar shear strength (ILSS) were compared and it was observed that although glass fibres are inferior to carbon fibres in terms of mechanical properties however, the flexure strength and ILSS of glass based composites increases after texturing and were found closer to the properties of carbon based composites.     

Performance of cotton single yarns and knitted fabrics produced by a 2-step spinning method

A low torque spinning method has been recently developed by integrating the ring spinning process with false twisting techniques. As a result of false twist and true twist, a novel single yarn of low torque and soft handle is generated. Based on the similar spinning principle, this paper proposed a 2-step spinning method, which is composed of twisting-anduntwisting operation and can be considered as a variant of the low torque spinning method. The proposed spinning method separates the false twisting process into twisting and untwisting processes which are combined in one step in the low torque spinning method. In this paper, physical properties of yarns produced by the proposed spinning method were evaluated and compared with the conventional yarns. Influences of various spinning parameters on the properties of 2-step yarns were also examined. Furthermore, a systematic study of the physical properties of the 2-step yarns and resultant fabrics with respect to the conventional and low torque ones was carried out. The experimental results showed that the 2-step yarns exhibit slightly higher tenacity, lower wet snarl and much less hairiness than the conventional yarns, which, however, are inferior to the low torque yarns, particularly the evenness. The fabrics made by the 2-step yarns show the softest handle feeling, best airpermeability and moderate spirality angle with acceptable pilling resistance.     

Effect of ultrasonic laundering on thermophysiological properties of knitted fabrics

The paper focuses on the application of ultrasonic energy in textile laundering. In recent years, there has been an increasing interest in ultrasonic energy application in textile industry; however, the effect of ultrasonic laundering on the thermophysiological properties of knitted fabrics has not been studied yet. This study was conducted by using polylactic acid (PLA), cotton, polyethylene terephthalate (PET), and poly acrylic (PAC) fibres containing yarns and their blends. Knitted fabrics, single pique, were made from these yarns by using weft knitting machine. The fabrics were washed ten times for 15 and 60 minutes under 40 °C by using conventional and ultrasonic washing methods. The main aim was to determine the effect of washing methods on the thermophysiological properties of the fabrics. It is also aimed to analyse and evaluate the thermophysiological properties of the PLA fabrics. The incorporation of 100 % PLA and cotton/PLA yarns into single pique knitted fabrics has been attempted to produce for the first time and studied their thermal comfort properties. The results show that the washing processes have a critical importance for the tested fabrics in terms of thermal conductivity, thermal resistance, thermal absorbtivity, water vapour permeability, and heat loss. It has been also demonstrated that the fabric cleaning by using ultrasonic method enhanced the properties of tested fabrics such as thermal conductivity and % recovery. It was also noted that 15 minutes ultrasonically washed fabrics had significantly lower thermal resistance as compared to conventionally washed fabrics.     

Electromagnetic shielding characteristics of woven fabrics made of hybrid yarns containing metal wire

In this study, electromagnetic shielding characteristics of woven fabrics made of hybrid yarns are investigated. For this purpose, initially the hybrid yarns containing stainless steel wire are produced with hollow spindle covering technique, and then eight different fabric samples are produced using these hybrid yarns. Electromagnetic shielding values of fabric samples are determined by a test set up based on enclosure measurement technique. Measurements are made in the frequency range of 30 MHz-9.93 GHz. Test results show that woven fabric samples investigated in this study have 25–65 dB electromagnetic shielding effectiveness for incident frequency. It was also shown that the direction, density and settlement type of conductive hybrid yarn in fabric structure are important parameters affecting electromagnetic shielding characteristics of woven fabrics.     

Dimensional stability of single jersey fabrics of LincLITE® and conventional yarns. I

Dimensional constants (k values) of single jersey fabrics made from LincLITE® and conventional yarns are calculated under dry, steam, full relaxation treatments. Fabrics were made under different tightness factors such as high, medium and low with different twist factors, twist directions and feeder blending. LincLITE® yarns made to get soft and bulkier effects with yarn count of 39 tex and conventional yarns made into 39 tex and 48 tex yarn counts. Various effects on K values are analysed using correlation coefficients. K-values are increased with relaxation progression and have shown some differences between in LincLITE® and conventional fabrics, and feeder blended fabrics. Loop shape factor is highly affected by tightness factor, relaxation and feeder blending in LincLITE® fabrics, whereas twist factor not significantly effects on loop shape factor in conventional fabrics. Stitch density significantly increases with relaxation in conventional fabrics and no significant effect shows with LincLITE® fabrics.     

Effect of temperature and activators on the characteristics of activated carbon fibers prepared from viscose-rayon knitted fabrics

This study used viscose rayon-based knitted fabric, pre-treated by a composite flame retardant, as the precursor. The fabric then underwent oxidation, carbonization and activation in a semi-open high-temperature erect furnace to produce Activated Carbon Fabrics (ACF). The microstructure and chemical properties of the ACF were obtained under carbonization temperatures of 600–1000 °C and by different activation sources. The results showed that the ACF produced was mainly of a microporous structure. When the carbonization temperature was increased, the production rate dropped while both the true density (D_He) and crystallization thickness increased. In addition, ACF prepared using steam, plus water as the activation source, has a larger specific surface area, greater crystallization thickness and a higher true density (D_He).     

The mechanical properties and abrasion behavior of warp knitted fabrics for footwear

The abrasion behavior of three kinds of warp knitted fabrics, which are normally used for upper sole of footwear, was evaluated. We measured the changes of mechanical and structural properties of each sample as abrasion cycle increased. Each sample showed similar trends in compression and surface properties but there were significant differences in abrasion rate among the samples. The mechanical properties showed remarkable differences with directions. The frictional coefficient (MIU) of fabric surface increased at the beginning of abrasion and decreased as abrasion cycles increased. The weight and thickness of the fabric linearly decreased with abrasion cycles. The surface roughness (SMD) and the compressional resilience (RC) decreased as abrasion cycles increased while compressional energy (WC) increased.     

Low stress mechanical properties of fabrics woven from bamboo viscose blended yarns

This paper presents the low stress mechanical properties of plain fabrics woven from cotton, bamboo viscose and cotton-bamboo viscose blended yarns. Three blends (100 % cotton, 50:50 cotton-bamboo and 100 % bamboo) were used to produce three yarn counts (20, 25 and 30 Ne). Each of these yarns was used to make fabrics with different pick densities (50, 60 and 70 picks per inch). It was found that bending rigidity, bending hysteresis, shear rigidity, shear hysteresis and compressibility is lower for bamboo fabrics as compared to those of 100 % cotton fabrics. On the other hand, extensibility, tensile energy and compressional resilience are higher for 100 % bamboo fabrics than 100 % cotton fabrics. Higher pick density increases linearity of load-elongation curve, bending rigidity, shear rigidity and compressional resilience. Shear and bending rigidities show very good correlation with the respective hysteresis values.     

The influence of corona discharge treatment on the properties of cotton and polyester-cotton knitted fabrics

In this study, the effect of corona discharge treatment on the physical and mechanical properties of bleached cotton and polyester-cotton fabrics were investigated. For this purpose, the samples were treated by corona discharge at two levels of voltage 5 and 10 kV, and at various duration times of plasma, ca. 1.4, 2.1 and 3.5 min. The corona discharge treatment was applied on the fabric samples before and after bleaching treatment. The results show that the corona influences on the surface morphology, breaking strength, air permeability, abrasion resistance, and pilling of cotton and polyester-cotton fabrics. Moreover, the levels of voltage and duration of plasma have a different effect on the properties of fabrics.     

Effect of hollow polyester fibres on mechanical properties of knitted wool/polyester fabrics

The physical and mechanical characteristics of hollow polyester fibres were compared with solid polyester fibres in order to establish their processing behaviour and performance characteristics. The effects of hollow fibres on fabric properties were investigated by using microscopy and tests of tensile and bursting strength, pilling, abrasion resistance, water vapour permeability, and handle. The results show that tensile strength of hollow polyester fibres and yarns are negatively affected by the cavity inside the fibre. Hollow fibres also have higher stiffness and resistance to bending at relaxed state. Fabrics made from hollow polyester/wool blends and pure wool fabrics show three distinguishable steps in pilling. During pilling, hollow fibres break before being pulled fully out of the structure, leading to shorter protruding fibres. Microscopy studies showed that the breakdown of hollow fibres started during entanglement by splitting along the helical lines between fibrils. KES results showed that the friction between fibres and the fibre shape are the most important parameters that determine the fabric low stress mechanical properties. However, in some aspects, the hollow structure of the fibre does not have a significant effect.     

Dimensional stability of single jersey fabrics of lincLITE® and conventional yarns. II. Fabric dimensional changes

Dimensional changes of single jersey fabrics made from LincLITE® and conventional yarns (39 tex and 48 tex) with different twist factors and fabric tightness factors are investigated under dry-, steam- and full- relaxation treatments. Results showed that linear and area shrinkages, fabric density and stitch density values were affected by tightness factors, relaxation treatment, yarn twist and feeder blending. Generally, higher length shrinkages and width increases were reported with LincLITE® and conventional fabrics. Tightness factors and twist factors significantly affected LincLITE® and insignificantly affected conventional fabrics in concern of change of shape and area shrinkages. Thus, fabric density values and reciprocal of stitch lengths showed linear correlations with intercepts, which decreased on full relaxation. Also, it showed higher regression correlation coefficient factors from LincLITE® and conventional fabrics.