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Compression socks are a highly acclaimed textile garment for pressure exertion on the lower part of the leg (ankle). This part of the research explains the theoretical investigation of compression pressure by the modelization technique that helped to develop two new mathematical models by incorporating a few missing parameters for the measurement of compression pressure (kPa) and compared with existing models simultaneously. These new parameters including deformed width ( wf), true stress ( σT), logarithmic strain ( εT), true modulus (ET), and engineering stress ( σE)/strain ( εE)/modulus (EE) were incorporated and compared with Hook’s law ( k = fx) used for elastic materials at the ankle position. Various brands of compression socks composed of similar fibrous combinations as well as the knit type were purchased. Initially they were hand-washed, put on the leg for marking, a square was marked, circular cut-strips were detached from the ankle portion of the compression socks, and they were then cut to a linear shape for all 13 sock samples. For this, all linear cut-strips were installed on a Testometric tensile testing machine and were extended to a fixed elongation of 65% of gauge length five times simultaneously, and were then extracted for different extension (mm) values considering the requisite practical elongation values (circumferential difference between leg and socks at the ankle portion). The models developed were compared with Hook’s law and Laplace’s law. The developed models were compared with compression pressure values measured using existing models statistically.

The utmost parameters that measure the thermo-physiological comfort of garments are thermal conductivity, thermal absorptivity and water vapor permeability. In this paper, thermo-physiological comfort was studied with different weave design and moisture content. Thermal properties and water vapor permeability in dry and wet state of all fabric samples were determined by ALAMBETA and Permetest respectively. Results showed that the weaving structure and yarn composition in weft were closely related to the thermal properties and water vapor permeability in presence of moisture. Woven fabric samples were constructed by varying the weave design and weft composition. In wet state, moisture content up to 20%, weave structures exhibited non-significant behavior for thermal properties due to air fraction. As the moisture content enhanced, woven structure made with polyester weft yarn provided cooler feeling with skin contact.

Comfort along with the aesthetic properties of textile clothing in activewear and sportswear are utmost worthwhile for costumer demand as latest trends. Different types of fibers and yarns are being used to improve the moisture management and comfort of the fabric for next to skin. Nowadays, multifilaments or nano-filaments of polyester with diameters in the range of a few nanometers and lengths up to kilometers are used in different range of important technological applications such as functional fabrics, biomedicine, composite, etc. Multifilament polyester yarns are made by aggregating many continuous filaments together characterized by their high tenacity and large surface area per unit mass. The nano-filament yarn has also significant effects on thermal comfort properties as a nano-filament fabric has less thermal conductivity than cotton fabric, but equal to multichannel polyester fabric while nano-filament fabrics gave the cool feelings with higher thermal absorptivity. Moreover,coolmax fabric showed the higher value of thermal resistance as compared to nano-filament fabrics. Nano-filament fabrics exhibited higher value of watervaporpermeability than cotton fabric.

Uyku tulumları ve uyku pedleri (şilteler), dağcılık sporunun vazgeçilmez ekipmanlarıdır. Uygun uyku tulumunun seçilmesi için en önemli özellik kişinin uyurken gerekli ısıl yalıtımını sağlamasıdır; ancak şilteden zemine doğru %40 ve daha fazla ısı kaybı meydana gelmektedir. Şiltelerdeki bu önemli kayba rağmen bu konuyla ilgili bir çalışma bulunmamaktadır. Bu çalışmada, kalınlıklarının arttırılması için boşlukları basınçlı hava ile şişirilmiş şilteler ile gözenekli poliüretan (PUR) köpükle doldurulmuş şilteler teorik ve deneysel olarak analiz edilmiştir. Yapılan teorik analizden, gözenekli PUR köpük yapılarına sahip şiltelerin şişirilmiş şiltelere göre iç boşluklardaki serbest konveksiyonun azalması nedeniyle yaklaşık 2 kat daha fazla ısıl direnç sergileyeceği bulunmuştur. Teorik analizle bulunan bu sonuç makalede verilen deneysel çalışma ile doğrulanmıştır, Sleeping bags and sleeping pads present inevitable equipment of all sportsman dedicated to mountaineering. Major part of thermal insulation of a person sleeping in a sleeping bag ensures the proper bag, but more than 40% of heat escapes through the sleeping pad (mattress) down to the ground or floor. However, despite the importance of sleeping pads, related research reports are almost missing. In the study, heat transfer mechanisms in hollow sleeping pads filled with the pressure air (to increase their thickness) and modern sleeping pads additionally filled with porous polyurethane foam is theoretically and experimentally analysed. From the theoretical analysis follows, that sleeping pads filled with porous polyurethane structures exhibit approximately 2 times higher thermal resistance then empty inflated pads, due to the reduction of free convection in the internal space of the pads. These theoretical findings were confirmed by the experimental results presented in the paper

This study aims to develop a model for the prediction of thermal resistance of fleece fabric by using regression analysis and artificial neural network technique. Primarily fleece fabrics protect human body from heat loss during cold weather. Its second purpose is to absorb sweat from human skin. Fleece fabric is commonly used to make sweatshirts, trousers, and jackets for cold weather. Higher thermal resistance of fleece is one of the main demands of users. Many factors can influence the thermal resistance efficiency of fleece. We have used porosity, thickness of fabric, thermal conductivity of fabric, overall moisture management capacity, thermal absorptivity, percentage of cotton, and polyester and planner weight as independent variables for the prediction of thermal resistance of fleece fabric. We have found that there was a significant difference between regression and artificial neural network analysis in the selection of most significant factor. Nevertheless, both models are significant. Moreover, we have also found that there is a significant correlation between two most significant variables selected during regression analysis and artificial neural network. Keeping all these in view, we can say that both models are capable of finding the thermal resistance of fabric despite the fact that artificial neural network techniques give better explanations

The most important parameters characterizing thermophysiological comfort of clothing are thermal conductivity and thermal resistance. Protective and sport clothing is often used in wet state, which influences their comfort properties. Wet state of clothing can be caused due to the absorption of sweat or moisture from humid environment. This effect was particularly applies to people staying on the sea - sailors, seamen as well as marine soldiers. In this paper, Alambeta fast working PC controlled tester, was used for determination of thermal resistance and thermal conductivity of five different woven fabrics and one knitted fabric containing 93-100% of Nomex fibres, both in dry and wet state. Moreover, the effect of salinity of real sweat or sea water was simulated, by adding 1%, 2% and 3% of salt into the testing liquid (distilled water). As follows from the original results, even small content of the sodium chloride salt influences thermal comfort properties of the wetted fabrics

Viskon, modal ve lyocell lifleri rejenere selüloz liflerinin üç versiyonu olup, doğal yapıları ve özellikleri nedeniyle tekstil ve çevre açısından en önemli liflerdendir. Konvansiyonel viskon, modal ve yeni lyocell liflerinin farklı üretim prosesleri ve üretim koşulları, aynı kimyasal yapıya sahip olmalarına rağmen lif yapılarında farklılığa yol açmaktadır. Bu çalışmada, viskon, modal ve lyocel lif ve ipliklerinin yapısal özellikleri araştırılmıştır. Ayrıca, liflerin yapısal özelliklerinin, bazı örme kumaşların boncuklanma, patlama mukavemeti, renk verimliliği ve termo fizyolojik konfor özellikleri üzerine etkisi incelenmiştir. Viskon liflerinden üretilen kumaşların boncuklanma eğiliminin lif yapısal özellikleri nedeniyle lyocel ve modal liflerinden üretilen ham kumaşlara göre daha fazla olduğu belirlenmiştir. Lyocel liflerinin mukavemetinin daha yüksek olması nedeniyle kumaş patlama mukavemetinin de daha yüksek olduğu belirlenmiştir. Lyocell liflerinden üretilen kumaşların ısıl iletkenliği daha fazla olup, viskon ve modal liflerine göre ilk dokunuşta daha serin hissi verdiği belirlenmiştir. Renk verimliliği en yüksek lyocel liflerinden üretilen kumaşlarla elde edilmiştir, Three generations of regenerated cellulose fibers, such as viscose, modal and lyocell fibers are among the most important fibers from the point of textile and environmental aspects due to the natural structures and properties. Different production process and production conditions for conventional viscose, modal and new lyocell fibers cause differences in the structure of the fibers in spite of the same chemical compositions. In this study, the structural properties of viscose, modal and lyocell fibers and yarns were investigated. Besides, the influence of structural characteristics of the fibers on the performance properties of knitted fabrics such as pilling, bursting strength, color efficiency and thermo physiological properties were determined. It was determined that due to the fiber structure, pilling tendency of viscose fabric is higher compared to lyocell and modal grey fabrics. Since the tensile strength of lyocell fiber is higher, fabric bursting strength of lyocell fabric is higher than the modal and viscose fabrics. As the thermal conductivity of lyocell fabric is higher, it gives cool feeling compared to viscose and modal fabrics. The highest colour efficiency is obtained from lyocell fabrics

Kumaş yüzeyi ile deri arasındaki sürtünme, giysilerin konfor performanslarını belirleyen önemli bir parametredir. Bu çalışmada farklı oranda elastan içeren örme kumaşlarda nem içeriğinin sürtünme katsayısına etkisi araştırılmıştır. Ölçümler Minho Üniversitesinde geliştirilip patent alınmış, kumaşların sürtünme katsayısının belirlenmesinde yeni bir metoda dayalı olarak ölçüm yapan FRICTORQ cihazı ile yapılmıştır. Kumaşta artan nem miktarı ile sürtünme katsayısının belirli bir limite kadar artmakta olduğu tespit edilmiştir. Yaklaşık % 40’ın üzerindeki nem değerlerinde sürtünme katsayısı sabit hale gelmektedir. Yarı elastan içeren ve en sık yapıdaki kumaşlar en yüksek sürtünme değerleri vermiştir, The friction between the skin and fabric surface is an important parameter characterising the comfort performance of garments. In this study, the effect of moisture on the friction coefficient of knitted fabrics containing different elastane ratios was investigated. The measurements were carried out by means of the FRICTORQ tester, a new patented measuring instrument developed at the University of Minho and based on a new method of determination of friction coefficient of fabrics. It was found that with increasing moisture level in fabrics, the friction coefficient increases as well, but just to a certain limit. The level of friction coefficient becomes stable over the moisture regain value of 40%. The fabrics which contain elastane yarn in every alternating course and the tight structures exhibit the highest fabric friction values

Comfort properties of textiles became important part of marketing of clothing with high added value in last decades. The most important parameters characterizing thermo physiological comfort of sport and protective garments are thermal resistance and water vapour permeability. Contrary to common textiles, protective and functional garments and some technical textiles are also used in wet state, which affects their comfort properties. However, these properties can be improved by application of special finishing agents. The objective of this paper is to investigate the effect of moisture on thermal comfort properties of 3 different cotton fabrics which were subject to 5 different finishing treatments. Thermal conductivity, thermal resistance, thermalabsorptivity and water vapour permeability of fabrics in dry and wet state were measured. Wet state of the studied fabrics was achieved by means of the so called “sweating impulse“. The achieved results were treated by means of advanced statistics and displayed in diagrams. It was found the presence of moisture affected substantively all thermal- insulation and thermal-contact properties.