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This paper aims to assess the relationships amongst the tearing strength of fabrics after each chemical processing stage and after finishing of plain-woven cotton fabric. An effort has been made to study the effect of different finishing chemicals (tear improver) and their different concentrations on the high-density fabric tear strength and its sub-component with respect to the co-efficient of friction value of yarns for all the fabric samples. It also aims to establish a statistical model for prediction of tear strength with identified parameters as yarn–yarn friction co-efficient, yarn pullout force and single yarn strength.

In case of woven fabrics, it cannot be assumed that only yarn friction plays the role in deciding fabric-tearing strength. Whether the static or kinetic frictions need to be considered or the linear or capstan frictions have to be analyzed, to incorporate the results of friction analysis in the tearing behavior, need to be assessed. In the present work through a fabrication of yarn–yarn friction measurement, under a synchronized slow speed as that of actual fabric tearing (50 mm/min), has been carried out. After each wet processing stage, surface characteristics of yarns have been changed. Surface of yarns becomes smoother after finishing and rough after dyeing, which affects the co-efficient of friction of yarns, accordingly.

After each wet processing stage, the surface characteristics of yarns are changed. Surface structure of yarns becomes smooth after finishing and rough after dyeing, which affects the co-efficient of friction of yarns. For all the fabrics, the weft-way tearing strength is always higher than warp-way tearing strength. It is also observed that yarn pullout force is not the only responsible factor for tearing strength of such fabric. It is because of the combined action of yarn–yarn friction, yarn pullout force and single yarn strength for a given structure.

A more extensive investigation with respect to concentration as well as further variety of chemicals requires to be identified for the optimum concentration level for each chemical. A mathematical model based on the three parameters as yarn–yarn co-efficient of friction, yarn pullout force and yarn strength for all woven fabric structure to achieve optimum strength level has been established which could be further extended for each fabric structures.

The problem has been identified from the day-to-day exercise of the commercial textile industry. The whole of the sample preparations have been done in the industry by using commercial machines under standard industrial conditions. The findings have been discussed and suitably introduced in the industry.

The whole of this paper has been unique in idea origination, sample preparation and execution of tests. The findings are very important for the researchers as well as for textile industry.

The purpose of this paper is to study the 100 percent pure cotton and 50:50 cotton and regenerated fibers (tencel, modal, bamboo, viscose) blends. The blends of regenerated fibers with cotton are studied so as to replace 100 percent cotton fabrics with the cotton blends as cotton cannot fulfill the demand of clothing due to the increasing population.

In order to conduct this study, cotton, as natural cellulose fiber, was used. Regenerated fibers include viscose, tencel, modal and bamboo. Five yarn samples of Ne 30/1 of 100 percent cotton and blends (50:50) of cotton with tencel, modal, bamboo and viscose fibers were produced. The blending was done in the Blow-room, and yarn samples were produced by employing the ring spinning technique. Plain woven fabrics samples with Ends (76) and Picks (68) per inch of 120 gsm were prepared. The fabric samples were tested for mechanical (warp and weft tensile and tear strengths) and comfort properties (air permeability, moisture management and thermal resistance).

Cotton:tencel fabric has the excellent mechanical (tensile and tear strength) as well as comfort properties (air permeability, moisture management and thermal resistance). It means that the most suitable blend that cotton can make with the regenerated fibers is the tencel. Therefore, to have more comfortable fabrics, the fabrics which are being made by 100 percent cotton can be replaced with the cotton:tencel.

To the authors’ information, no study has been reported in which all the regenerated fibers blended with cotton were studied. Hence, the aim of this work is to study the mechanical and comfort properties of the regenerated fibers (modal, tencel, viscose and bamboo) blended with cotton. The blends of cotton with regenerated fibers might replace 100 percent cotton in clothing applications as cotton cannot fulfill the increasing demanding of clothing.

The purpose of this research is to propose a flexible sensor with a weft-knitted float stitch structure and to explore knitting techniques that allow conductive yarns to be skin-tight and less exposed, reducing production processes and increasing productivity. Study its electrical conductivity in different yarn materials, knit processes and deformation ranges. The analysis is compared to provide some basis for the design of the electrodes.

The method includes five operations: (1) Analysis of the morphological appearance, tensile variation, fiber material properties and electrical conductivity of high-elastic and filament silver-plated conductive yarns. (2) Based on the knitting process of the floating yarn structure, three-dimensional modeling of the flexible sensor was carried out to explore the influence of knitting process changes on appearance characteristics. (3) The fabric samples are knitted by different silver-plated conductive yarns with different structures. Processing of experimental samples to finished size by advance shrinkage. (4) Measure the resistance of the experimental sample after the machine has been lowered and after pre-shrinking. Use the stretching machine to simulate a wearing experiment and measure the change in resistance of the sample in the 0–15% stretching range. (5) Analyze the influence factors on the conductive performance of the flexible sensor to determine whether it is suitable for textile flexible sensors.

For the float knitted flexible sensors, the floating wire projection is influenced by the elasticity of the fabric and the length of the floating wire. Compared to the plain knitted flexible sensors, it has less resistance variation and better electrical properties, making it suitable for making electrodes for textile structures. In addition, the knitting method is integrated with the intelligent monitoring clothing, which saves the process for the integration of the flexible sensor, realizes positioning and fixed-point knitting.

The sensor technology of the designed weft-knitted float structure is varied and can be freely combined and designed in a wide range. Within the good electrical conductivity, the flexible sensor can realize integrated knitting, positioning monitoring, integrating into the appearance of clothing. It can also focus on the wearing experience of wearable products so that the appearance of the monitoring clothing is close to the clothes we wear in our daily life.

In this paper, an integrated positioning knitting flexible sensor based on the weft knitting float structure is studied. The improved knitting process allows the sensing contact surface to be close to the skin and reduces the integration process. The relationship between the exposure of the silver-plated yarn on the clothing surface and the electrical conductivity is analyzed. Within a certain conductive performance, reduces the exposed area of the conductive yarn on the clothing surface and proposes a design reference for the flexible sensor appearance.

This paper seeks to report an experimental investigation on the tearing and tensile strength behaviour of military khaki fabrics from grey to finished process.

Uses three different types of military fabric (3 up 1 down twill), differing in type of constituent yarns (ring/rotor) in order to test their tearing and testing strength behaviour.

Tearing strength of fabric is found to be very much susceptible to change due to the process variation, while fabric tensile strength is relatively less sensitive. Ring spun yarn fabric shows higher tearing strength compared with rotor spun yarn fabric. However, the difference in their tearing strength reduces substantially as the process approaches towards the finished state. On the other hand, rotor spun yarn fabric exhibits higher tensile strength along the warp. Tearing strength along bias direction is in between warp and weft wise tearing strength; whereas tensile strength is lowest while tested along the bias direction. During the grey to finished process, tear strength falls at bleaching and dyeing, and particularly drops in strength is being more at the dyeing stage.

This study has investigated the tearing and tensile strength behaviour of military khaki fabrics from grey to finished state, developing understanding of the impact of different processes on the tearing strength, so that fabric of the required tear strength can be developed with process modification.

In recent times, stretch denim garments have become very popular amongst consumers as the garment is able to provide body fit and body comfort at the same time. The purpose of this study is to investigate the effect of abrasion on the change in surface appearance, mass loss and ultimate tensile properties of the stretch denim fabric in different directions (warp, weft and biased).

After abrading the fabrics in three different directions (warp, weft and biased), the loss in ultimate tensile properties, mass loss and surface appearance has been investigated in the respective directions of abrasion (warp, weft and biased). The study also encompasses the effect of different types of stretch yarn with varying levels of elastane content on such unidirectional abrasive damage.

It is seen that with the same level of abrasion cycles, the fabric's response in terms of mass loss and loss in ultimate tensile properties are different in different directions. The mass loss due to abrasion in biased direction is found to be minimum. The loss in ultimate tensile properties due to abrasion was highest in the weft direction. It is also found that the higher mass loss due to abrasion does not always result in a greater loss in ultimate tensile properties. The composition and the structure of the weft yarn significantly affected the extent of the mass loss and the loss in ultimate tensile properties during abrasive damage.

The impact of abrasive damage in terms of mass loss and loss in tensile strength along the different directions of denim fabric has not been explored till date. Abrasion of fabric can be done both in multi-direction (Lissajous motion) as well as in uni-direction (linear motion). The multidirectional abrasion provides a holistic or comprehensive idea of the fabric's response to the abrasive damage but does not take into consideration the fabric's anisotropic response to the abrasive damage. Most of the earlier investigation related to abrasive damage of denim fabric has been done in instruments where the motion of the abrader is multidirectional (Lissajous) in nature. For greater depth of understanding about the fabric performance under abrasive damage along the various direction (warp, weft and biased), unidirectional abrasion is conducted in this study.

The purpose of this study is to investigate the mechanical properties of denim fabrics constructed from ring-spun and open-end rotor spun yarns.

Yarns of 10s Ne count using cotton fibers were spun using the ring and open-end rotor spinning technologies. The yarns were used to produce a denim fabric on an air-jet loom with a 3/1 twill weave structure. Mechanical tests – tensile strength, tear strength, abrasion resistance and pilling resistance – of denim fabrics were evaluated. The test results were analyzed using analysis of variance with the help of Software Package for Social Sciences.

Denim fabrics made by using ring-spun yarns exhibited better tensile and tear strength properties than denim fabrics made by using open-end rotor spun yarns. On the contrary, denim produced using open-end rotor yarns have better abrasion resistance, pilling resistance and air permeability than those produced using ring-spun yarns.

Both spinning techniques have a significant influence on the properties of denim fabrics. Whenever better tensile and tear strength is required, it is better to use ring-spun yarns, while if the requirement is better abrasion resistance and pilling resistance with high air permeability, then open-end rotor spun yarns shall be used.

The tensile properties of spun yarns are accepted as one of the most important parameters for the assessment of yarn quality. Tensile properties contribute to the performance of post spinning operations; warping, weaving and knitting, hence their accurate technical evaluation carries much importance in industrial applications. This article presents a novel approach of classification of tensile properties into static and dynamic, based on the disposition of yarns during tensile testing. The definition of dynamic tensile properties and instruments utilized for their assessment are briefly discussed. Several theoretical and experimental work pursued on the static and dynamic tensile properties of ring, rotor, air-jet and friction spun staple yarns are critically reviewed. The article also throws light on the significance of exploitation of spun yarn dynamic tensile properties in industrial applications. The various material, spinning and testing parameters that influence static and dynamic tensile properties are summarized. The reported empirical equivalence of static and dynamic yarn strength of spun yarns is revealed. Current research work in the thrust area of spun yarns that are subjected to dynamic conditions is introduced.

The purpose of this paper is to conduct a series of tests designed to highlight changes in the physical characteristics of the yarn resulting from mechanical efforts comparable to that to which they are subjected on the weaving machine. Among the physical properties of the warp yarn, the authors examined changes include: the residual deformation, strength, elongation and elasticity, on the extender repetition effort overtension growing steadily, leading, after some time, to break. Therefore, the yarn treated extender repetition is subject to a more severe test than the actual weaving on the loom.

The initial length of the specimen under constant static load of 20 g, was 50 cm in all tests. The yarns are stored on several coils, the authors collected a quantity of thread on each of them, according to the law of chance, to avoid errors due to long periods of irregularity and the authors estimated that the extensions can be supported by the wire without danger of rupture are interesting practical point of view. Three rate extensions were chosen for the two yarns: 0.5, 1.2 and 1.9 percent. The maximum number of tractions was calculated for each wire by multiplying the maximum thread count practice by the average distance between the warp beam and the weft yarn on the weaving machine.

The fall of the resistance and elongation resulting from repeated extensions which yarn are subjected on the extensometer, corresponds almost exactly to the residual deformation recorded. Increasing the rate of extensions causes relatively large decrease in strength and elongation. The authors also notice that the strength and elongation at break tends to decrease when the number of extensions decreases. The fall of the resistance and the elongation at break is more important for carded yarns then combed yarns increases or when the frequency decreases.

The maximum difference of the resistance is 32 g, 10.3 percent in the case of carded yarns, while in the case of the combed yarns; the same difference is 25 g, or 6.4 percent of the initial strength. Similarly, the maximum fall of the elongation at break for carded yarns is about 2 or 16.1 percent of the initial elongation, while the corresponding drop in the case of the combed yarns is 1.8 or 10.9 percent of the initial elongation. The corresponding values found during the testing wool combed yarns, were, respectively about 4.8 and 6.6 percent.

No study was published about the tensile properties of different sections of multicount yarn. Hence there was a need to conduct a detailed section-wise tensile study of fancy multicounty yarn. The purpose of this study is to identify the different sections of the same multicount yarn and test them separately.

Multicount yarn with slubs were prepared on a ring frame with the Amsler Textile Effect System. Different yarn sections from each multicount yarn are identified as fine normal, fine slub, medium normal, medium slub, coarse normal, coarse slub and the changeover sections. These sections are tested for the breaking load and breaking elongation. Broken ends of the yarn sections are also studied, and these broken ends are classified as sharp broken end, tapered broken end and slipped broken end. A study is also conducted on the location of break or the place of break at the changeover sections.

It was found that the twist of yarn at slub sections was lower than the twist at normal sections. In spite of the low yarn twist at slub sections, the breaking load of the yarn was higher at slub sections than at normal sections by 12 to 30 per cent owing to the presence of more number of fibres that share the breaking load. The breaking load at the changeover section (normal to slub and slub to normal) was found to be higher than that at normal section and lower than at slub sections. No significant difference was found between the breaking load of the two changeover sections (normal to slub and slub to normal). The majority of breaks in normal yarn sections were of the tapered broken end type and the majority of breaks in slub yarn sections were slipped broken ends.

Efforts are taken to identify different sections of the same multicount yarn with the help of specially designed square black board and tensile study of these sections are carried out.

The traditional Japanese cotton-crepe fabric chijimi has been used for summer clothing for over a century because of its good skin comfort. The high extensibility of this fabric relies on the high-twist cotton yarns used in the weft direction. The purpose of this paper is to show the effect of environmental humidity on the extensibility of highly twisted cotton yarns to help in choosing weft yarn suitable for woven fabric.

Four highly twisted cotton yarns are examined under 10-90 percent RH and in 25°C water. Cyclic tensile tests are performed to obtain the tensile energy, resilience, extensibility at maximum applied load (EM), and residual strain.

Comparing the same yarn-count samples Y1 and Y2, the EM of Y2 (2,200 T/m) is larger than that of Y1 (1,000 T/m) under all RH conditions, and the difference increases at humidity over 60 percent RH. For fabric crepe samples woven by Y1 (warp) and Y2 (weft), the extensibility (EM-1) in the weft direction is in the range 16-26 percent, which is equivalent to that of outer-knitted fabrics. The extensibility and recovery of chijimi is largely dominated by the twist of weft yarns, which is also influenced by changes in relative humidity.

The skin comfort of Takashima chijimi has been of interest, but the high extensibility of this cotton fabric has not been given much attention. The results of this study show that yarn twist is key to controlling extensibility in high-humidity environments.