Thermo physiological comfort of single jersey knitted fabric derivatives

The main aim of this study is to determine the thermo-physiological comfort properties of single knit fabrics and their derivatives. As the Single Jersey knitted fabrics are the most widely used fabrics in the apparel sector, they have been selected for the analysis purpose. Derivatives of single jersey are developed and compared in order to understand the influence of structural variations. Physical properties e.g. thickness and areal density were evaluated for all knitted fabrics with 100% cotton yarn having three different yarn linear densities and after different stages of relaxation. Various thermo-physiological properties have been studied by changing the combed cotton yarn linear density as well as the structure of single knit fabric. Air permeability, thermal insulation and relative water vapor permeability of the fabrics were observed and investigated under wet relaxed states. It is determined that fabric physical properties are affected by changing yarn linear density and by the dry or wet relaxation stages. The percentage/number of tuck stitches (NTS), location of tuck stitches (LTS) and ratio of tuck to knit stitches (RTKS) have strong influence on physical and thermo-physiological properties of single knit fabrics, even though other knitting parameters remained the same.

Investigation of Dimensional and Physical Properties of Eri Silk Bi-Layer Knit Fabrics for Active Wear Applications

The knitwear industry caters to the needs of the modern youth, whose preferences vary according to the trends and tastes of the modern age. This paper endeavors to demonstrate that active wear fabrics made of eri silk have very good physical properties. The main objective of this research is to investigate dimensional and physical properties of plated interlock, mini-flatback rib, and flatback rib structures developed with two different yarn counts (30s and 40s). The dimensional and physical properties of those samples are investigated in terms of dimensional stability, spirality, bursting strength, elongation percentage, fabric areal density, and fabric thickness. Variables such as yarn count and knit structure play a significant role on the dimensional and physical properties of the fabric.

Structural Impact on Some Common Physical Properties of Single Jersey Weft Knit Fabric

Single jersey weft knit fabrics include a large portion of knitted products. These fabrics are made using different types of stitches. In this study, several single jersey weft knit fabric samples containing four courses and two wales in the repeating unit of the fabric structure were made by introducing and gradually increasing the number of tuck stitches in the structure, to find out the effect of this stitch on fabric properties. Results showed that tuck stitches could positively affect the areal density, width, and tensile properties of the fabric. For some comfort-related properties, tuck stitches were found to improve wicking and drying properties, reduce water vapor transmission rate, and affect fabric smoothness. The position of tuck stitches in the structure also had some effect, but was not as significant as when the number of tuck stitches was varied.

A critical study of the effects of flame retardancy on different knit fabrics

A novel flame retardant especially Pekoflam HFC was synthesized to improve the flame retardancy of fabric. Pekoflam HFC is especially suitable for flame retardant back coatings of synthetic fibre based home textiles and high-performance technical textiles. The flame retardancy of the samples was characterized by the spray method and the vertical burning test. The results indicated that the flame retardant had excellent flame retardancy and durability for cellulosic fabrics. The cotton knit fabric treated with Pekoflam HFC obtained the optimum flame retardancy with the decreased char length. Combustion behaviors of treated cotton fabric were tested by manual observation. After treatment, it found that the ignition time increased, and the values of total heat release, heat release rate and mass loss decreased. The strength and durability of treated fabric were studied by tear force test and washing durability test, respectively.

Functional Textile for Active Wear Clothing

Moisture management property is an important aspect of any fabric meant for active wear fabric, which decides the comfort level of that fabric specially used as active wear garments. Regular physical activity is important to maintain consistency in human health. To achieve comfort and functional support during various activities such as walking, stretching, jogging etc., athletes and sports persons use active wear clothing. A fabric’s moisture management performance is also influenced by its air and water vapour permeability. The moisture management finish (MMF) and Antimicrobial finish (AMF) have been used to increase moisture absorbency; improves wetting, wicking action and antimicrobial performance. In this study, influence of MMF and AMF finishes on the moisture management property of different knitted active wear fabrics had been carried out. For the study two different knit fabrics of 100% Polyester and 100% Nylon with three different GSM levels (100, 130 and 160) has been selected. Further two varieties of commercially available functional fabric finishes have been also taken for the study. The result shows that in case of finished fabric at certain concentration level, as the fabric GSM increases the value of Accumulative one-way transport index (OWTI) %, water vapour permeability but same time drying rate increases. The result shows that in case of finished fabric at certain concentration level, as the fabric GSM increases the value of accumulative one-way transport index (OWTI) %, water vapour permeability decreases but same time drying rate increases. The knitted fabrics of 100% Polyester and 100% Nylon composition follow the similar trend. Further with the increase of fabric finish concentration level, OWTI %, and water vapour permeability (WVP) factor decreases while the drying rate increases.

Study on Special Shaped Polyester Fibers and Development of Products

Non-circular profiled fibers are generally synthetic fibers that have a modified cross-section shape, which are created to mimic natural fibers or to obtain special properties. The shape of the cross-section has great influence on the properties of profiled polyester (PET) fibers and their fabrics. The structure and properties of flat-shaped and hexagonal-shaped profiled PET fibers and ordinary PET fibers, as well as the properties of their knit fabrics were characterized. Experimental results showed that air permeability, heat retention, and wrinkle resilience of profiled PET fabrics were better than that of circular a cross-section PET fiber fabric, while the circular cross-section PET fabric was softer than the profiled PET fiber fabrics.

Manufacturing Color-Blended Slub Yarn: Computer Numerically Controlled Ring-Spinning Frame and Kubelka-Munk Double Constant Theory

In the present work, we used the computer numerically controlled (CNC) ring-spinning frame to produce the color-blended slub yarns made from three different colored rovings with a 10% blending gradient. The blending ratio of rovings was determined by Kubelka-Munk (K-M) double constant theory. The as-manufactured yarns were made into knit fabrics with a circular knitting machine. The relative value method was used to solve the absorption and scattering coefficients of each colored fiber, and the least-square method was used to solve for the blending ratio of color-blended slub yarn. The results show that the average color difference between predicted and measured L*a*b* values was 1.74, and the error of the blending ratio was 7.38%, which are within the acceptable ranges for color matching of yarns.

Thermal and moisture behavior of a multi-layered assembly in a pneumatic compression device

The objective of this research was to determine the effect of multiple layers of materials typical of those used in air pneumatic compression devices (which require air impermeable layers to function) on thermal and water vapor resistance. The experimental set-up included: (a) single layers of two next-to-skin knit fabrics in both relaxed and extended conditions, (b) two layers of silicone, and (c) a multi-layered assembly comprised of a next-to-skin fabric and two layers of silicone. Structural properties (thickness, mass) dominated thermal resistance of the multi-layered assembly, and the silicone layers rendered this assembly impermeable to water vapor as expected. Results confirmed the need for some form of 'ventilation' to facilitate water vapor transfer from a potential user’s skin to the environment. By creating 18 circular vents across the silicone layers (each vent 314 mm2), which formed ventilation of ∼2% of total surface area, the water vapor resistance of the multi-layered assembly dropped significantly from very high (but non-measurable) to below ∼300 m2 Pa/W, although ventilation did not improve the thermal resistance of the multi-layer arrangements. Results of this research will enable manufacturers of pneumatic compression devices to develop devices comprised of a multiple layer arrangements i.e. a knit fabric next-to-skin layer and silicone layers with optimized vents across the silicone layers, so that the user can continue the compression treatment with an acceptable microenvironment.

Development and Washing Reliability Testing of a Stretchable Circuit on Knit Fabric

The smart textiles and wearable technology markets are expanding tirelessly, looking for efficient solutions to create long-lasting products. The research towards novel integration methods and increasing reliability of wearables and electronic textiles (e-textiles) is expanding. One obstacle to be tackled is the washability and the endurance to mechanical stresses in the washing machine. In this article, different layering of thermoplastic polyurethane (TPU) films and knit fabrics are used to integrate three different designs of stretchable copper-based meander tracks with printed circuit boards. The various combinations are washed according to the ISO 6330-2012 standard to analyze their endurance. Results suggest that one meander design withstands more washing cycles and indicate that the well-selected layer compositions increase the reliability. Higher stretchability together with greater durability is accomplished by adding an extra meander-shaped TPU film layer.