Electrically conductive yarns (ECYs) are gaining increasing applications in woven textile materials, especially in woven sensors suitable for incorporation into clothing. In this paper, the effect of ...the yarn count of ECYs woven into fabric on values of electrical resistance is analyzed. We also observe how the direction of action of elongation force, considering the position of the woven ECY, effects the change in the electrical resistance of the electrically conductive fabric. The measurements were performed on nine different samples of fabric in a plain weave, into which were woven ECYs with three different yarn counts and three different directions. Relationship curves between values of elongation forces and elongation to break, as well as relationship curves between values of electrical resistance of fabrics with ECYs and elongation, were experimentally obtained. An analytical mathematical model was also established, and analysis was conducted, which determined the models of function of connection between force and elongation, and between electrical resistance and elongation. The connection between the measurement results and the mathematical model was confirmed. The connection between the mathematical model and the experimental results enables the design of ECY properties in woven materials, especially textile force and elongation sensors.
In recent years, more and more researchers have been focused on electrically conductive textiles that generate heat or transmit electrical signals and energy to embedded electrical components. In ...this paper, the dissipation of heat due to the flow of electric current at given voltages is investigated, and at the same time it is determined how this heat affects the change in the electrical resistance of the electrically conductive yarn in the immediate surroundings. Three fabric samples were woven in a plain weave with three types of different electrically conductive yarns. Three electrically conductive yarns are woven in parallel in the weft direction and separated from each other by one polyester (PES) yarn due to electrical insulaton. Conductive yarns are electrically connected so that the outer yarns are used for heating by the flow of electric current at a certain constant voltage, and the central yarn is used only to measure changes in electrical resistance. When electrothermally conductive fabrics are subjected to certain voltages over time, experimental results have shown that resistance values increase over a short period of time and then gradually decrease, while the temperature gradually increases and stabilizes over time. Based on the analysis of the obtained results of the ratio between the values of applied voltage and temperature to the electrically conductive yarns, the value of thermal dissipation in conductive yarns can be calculated in advance depending on the applied voltage. Furthermore, the obtained results can be further used in applications where conductive yarns are used as heaters for realistic prediction of the obtained heat.
Determination of mechanical properties and predicting the behavior of knitted fabrics during the manufacturing process and finally in the use is an important part of textile science. In this study ...the influence of knitted fabric anisotropy on the values of maximum force, corresponding extension and total work when axial tensile forces act on specimens cut at different angles with respect to the course direction of the knitted fabric were analyzed. A plain double weft knit fabric made of single cotton yarns was studied. For different angles of cutting samples, the curves of the relation between the values of the tensile forces and the extension at break were experimentally obtained. The mathematical models obtained were compared with the experimental results, and the corresponding correlation coefficients were calculated.
Elastic knitted fabrics find numerous applications in the industry for compression stockings, sports and leisure wear, swimwear, ballet wear, etc. During its use, knitwear is subjected to dynamic ...loading due to body movements. The loading and unloading of the knitted fabric affect the size of the elastic region in which unrecovered deformation completely disappears. This paper deals with the influence of the elastane percentage in the knitted fabric on the elastic properties of the knitted fabric under dynamic loading. For this experiment, three types of yarn were used in different combinations: polyamide (PA), wrapped elastane yarn and bare elastane. The mentioned yarns were used to knit three different groups of plated weft-knitted fabrics (two yarns in a knitted fabric row): without elastane, knitted fabric with a percentage of wrapped elastane, and knitted fabric with a percentage of bare elastane. The percentage of elastane ranged between 0% and 43%. First, standard uniaxial tensile tests were performed on knitted fabric samples until breakage under static load. The force–elongation diagrams obtained are used to determine the elastic limit up to which Hook’s law applies. All knitted fabrics were cyclically tested to the elastic limit. From the obtained loading and unloading curves, unrecovered deformation (unrecovered elongation), elastic elongation and hysteresis index were determined and calculated. The results showed that the percentage of elastane significantly affects the size of the elastic region of the knitted fabric and has no effect on the hysteresis index. Therefore, it is necessary to optimize the elastane percentage for different knitted fabric designs to achieve the best dynamic recovery of the knitted fabric and to design a more stretchable knitted garment that fits the body as well as possible.
Cultural heritage textile artifacts that have been preserved only in their smaller fragmented remains represent a very interesting and complex matter, very rarely analyzed and studied individually as ...a separate entity. This case study covers multidisciplinary research conducted on two 18th century silk fragments with a seemingly identical pattern. Demonstrating the possibilities and challenges which arise when analyzing and interpreting incomplete cultural heritage textile materials, this study can serve as a stimulus for creating a large-scale database of historical fabrics which would allow comparison based on their differences or common characteristics. By applying only non-destructive and micro-analytical methods it has been determined that the fragments were made of the same material and using the same manufacturing techniques. It has been proven that fragments were not part of the same historical fabric, but most likely originated from different parts of the same liturgical vestment. The reverse engineering process applied to preserved fragments has resulted in a detailed technical documentation and a complete reconstruction of the lost original pattern.
This paper lays out standards of compression stockings and their classification into classes. The analysis of knitted fabric structure parameters, elongation and compression of moderate- and ...high-compression stockings was conducted. Stocking compression on specific parts of the stocking leg was measured on three sizes of a wooden leg model. For moderate-compression stockings, compression above the ankle was 32 hPa. For high-compression stockings, compression above the ankle was 60 hPa. Both groups of the analyzed compression stockings were made on modern one-cylinder hosiery automats. The legs of the stockings were made in single inlaid jersey 1 + 1. Both yarns were elastane covered. The finer yarn formed loops and its knitting into a course was significantly larger than in the other yarn, which was much coarser and does not form loops but "lay the weft in a bent way". The smallest elongation of knitted fabric was above the ankle, where the highest compression was achieved, while the largest elongation was under the crotch, where the stocking leg exerted the smallest compression on the surface. The leg of the compression stocking acted as a casing that imposed compression on the leg and often reinforced it to be able to sustain compression loads.
This paper deals with the impact of fabric density on fabric thickness change when samples are subjected to uniaxial tensile forces in the weft direction. During stretching, fabric thickness changes ...depending on the value of the tensile force. In an effort to be as precise as possible in measuring fabric dynamic thickness changes and the area on which the tensile force acts, a new measuring apparatus was designed and constructed. This measuring apparatus allows the simultaneous measurement of fabric dynamic thickness, related tensile axial forces and extension. Measurements of the fabric dynamic thickness, breaking force and breaking extension during the stretching process were carried out on five samples of cotton woven fabric with a constant warp density and different weft densities in the same structural plain weave. Based on the experimentally obtained values, the paper presents diagrams of the relationship between dynamic changes in fabric thickness in relation to the tensile force and extension. The research presented in this paper shows that an increase in the tensile force increases fabric thickness for all weft densities. Also, the out-of-plane woven fabric ratio was calculated as a relation between the relative thickness strain and relative axial strain. The characteristic curve shows this ratio.
Textile materials are an essential part of contemporary architecture, the environment, and urban spaces due to their unique appearance and qualities, as it is now possible to achieve both a ...structural function and an aesthetic quality with textiles. As colour is one of the most important characteristics of textile material, it is also important to understand the relationships between colour and textile material with different surface qualities. In order to explain the complexity of different textile materials and the appearance of colours, which consequently affects the colour properties, this paper analyses this phenomenon. The presented research analyses the dependence of the reproduction quality and colour appearance on fabrics of different construction and structural characteristics, i.e., the texture of the textile material, printed using digital inkjet technology. The aim of this work is to investigate the influence of various structural features of textiles on the colour appearance of digitally printed textile substrates, to monitor the quality of colour reproduction, and to analyse the behaviour of a reactive dye droplet on textile substrates. Printing of a particular shape was performed using a Dimatix Materials Printer DMP-2831 piezoelectric inkjet device (provided by the J. Stefan Institute, Ljubjana, Slovenia; manufactured by Fujifilm Dimatix Inc., 2230 Martin Avenue, Santa Clara, CA, USA). The behaviour of the ink delivered by the needle of the tensiometer DSA20E, Kruess GmbH (provided by the J. Stefan Institute, Ljubjana, Slovenia; manufactured by Kruess Scientific Instruments (Shanghai) Co., Ltd. Futong Dong Dajie 10 Baoneng Center, Tower B, Room 605 Chaoyang District, Beijing 100102, China), on the surface of the fabric was analysed. The samples were digitally printed on a Mimaki digital printer Tx2-1600 (provided by University of Ljubljana Faculty of Natural Science and Engineering, Slovenia EU; manufactured by Mimaki, 2182-3 Shigeno-Otsu, Tomi-city, Nagano, Japan), with reactive dyes, which were first pretreated in a bath with a specific solution. The statistical method of image analysis and microscopic imaging were used to obtain the characteristics of the porosity, texture, and roughness parameters. All results are presented from colouristic analysis based on the objectification of colour and colour differences. The objective values of the parameters of lightness (L*), chroma (C*), and hue (h°) show the significant influence of the structure and properties of the substrate on colour reproduction, and significant changes were obtained, which were confirmed by the evaluation of the colour differences. The results confirm the influence of the substrate structure on colour properties. Furthermore, it is essential to consider this complexity in the context of environmental colour design when utilising (coloured) textile installations/materials in architecture and urban spaces, i.e., in the environment.
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