Investigation on thermo-physiological and compression characteristics of weft-knitted 3D spacer fabrics

The thermo-physiological comfort and compression properties of knitted spacer fabrics have been evaluated by varying the different spacer fabric parameters. Air permeability and water vapor transmission of the fabrics were measured using the Textest FX-3300 air permeability tester and PERMETEST. Thermal behavior of fabrics was evaluated by (TCi) thermal conductivity analyzer and overall moisture management capacity was evaluated by moisture management tester. Spacer fabrics compression properties were also tested using KES-FB3. In the KES testing, the compression resilience, work of compression, linearity of compression, and other parameters were calculated from the pressure–thickness curves. Analysis of variance was performed using new statistical software named QC expert trylobite and Darwin in order to compare the influence of different fabric parameters on thermo-physiological and compression behavior of samples. This study established that the raw materials, type of spacer yarn, density, thickness, and tightness of surface layer have significant influence on both thermal conductivity and work of compression in spacer fabrics. The parameter which mainly influences the water vapor permeability of these fabrics is the property of raw material i.e. the wetting and wicking properties of fibers. The Pearson correlation between moisture capacity of the fabrics and water vapor permeability was found.     

Thermo-physiological comfort properties of double-face knitted fabrics made from different types of polyester yarns and cotton yarn

Double-face knitted fabrics with hydrophobic inner and hydrophilic outer layers are characterised by their advantageous thermo-physiological comfort property that facilitates the transport of sweat from skin to outer fabric layer where it can be evaporated easily. In this study, for the production of double-face knitted fabrics, cotton yarn as hydrophilic yarn type and five different polyester filament yarns consisting of standard polyester, hollow polyester, micro polyester, textured polyester and textured micro polyester as hydrophobic yarn type were used. In order to determine the thermo-physiological comfort properties of the fabrics, air permeability, water vapour permeability, thermal conductivity, thermal resistance and overall moisture management capacity were measured. The results were comparatively analysed using statistical methods. The experimental results demonstrated that the polyester-type yarns and the combinations of them with the cotton yarn in fabric layers affected the thermo-physiological comfort properties significantly. The fabrics with polyester-type inner face and cotton outer face showed the best moisture transmission properties.     

Prototyping and analyzing physical properties of Weft knitted spacer fabrics as a substitute for wound dressings

In this research, the required physical properties of weft knitted spacer fabrics, as an alternative for wound dressings have been investigated. For this purpose, weft knitted spacer fabrics with five different fabric structures have been produced on the electronic flat knitting machine. Moreover, in order to compare the properties of the produced fabrics with available wound dressings in the market, two kinds of wound dressing have been prepared from the market. Then, the physical properties of the spacer fabrics and the wound dressings such as air permeability, water vapor permeability, thermal conductivity, compressibility and absorbency have been measured and compared. The results show that in weft knitted spacer fabrics with the same fabric structure of the outer layer and different inclination angle (the angle formed between the outer layer and the spacer yarn), by decreasing the inclination angle, the fabric air permeability, water vapor permeability and absorbency decrease and the thermal conductivity and compressibility increase. Moreover, the use of tuck stitches in the outer layer of the spacer fabric leads to an increase of air permeability, water vapor permeability, absorbency and thermal conductivity and decrease of compressibility. The wound dressings also exhibit less air permeability and compressibility than weft knitted spacer fabrics. On the other hand, they possess higher water vapor permeability and absorbency. According to the results, among the examined weft knitted spacer fabrics in this research, the fabric with the tuck stitches in the outer layer is specified as the most appropriate alternative for wound dressing, in case of wounds with low exudates.     

Steady-state thermal comfort properties of fabrics incorporated with microencapsulated phase change materials

This study focused on assessing the thermal comfort properties of the fabrics incorporating microencapsulated phase change materials (microPCMs) under steady-state condition. Air permeability and water vapor permeability of the fabrics were also investigated. Poly(methyl methacrylate)/n-hexadecane microcapsules were applied to the cotton and cotton/polyester fabrics using pad-cure methods. Thermal comfort properties of the fabrics were measured using Alambeta. The results indicated that the thickness of the fabrics incorporated with microcapsules increased depending on the amount of microcapsules added on the fabric. Thermal conductivity of the fabrics treated with polyurethane (PU) resin decreased while addition of microPCMs had almost no effect on the thermal conductivity. However, thermal resistance of the fabric increased as the fabric thickness increased or the thermal conductivity decreased. Air permeability and water vapor permeability of the fabrics treated with microPCMs were found to be lower than those of pristine fabrics while water vapor permeability of the fabrics treated with PU was found higher than pristine fabrics.     

A study on thermophysiological comfort properties of fabrics in relation to constituent fibre fineness and cross-sectional shapes

The present study reports the effect of linear densities and profiles of polyester fibres on the physiological properties of their fabrics. Four different polyester fibre finenesses along with microdenier and four cross-sectional shapes (circular, scalloped oval, tetrakelion and trilobal) were selected to produce two sets of 2/1 twill fabrics; one composed of 100% polyester and the other 67:33 P/V blends. In studying the thermophysiological component of the clothing comfort, heat, air and moisture transmission characteristics of the fabrics were assessed. The principal thermal properties, such as thermal absorptivity, thermal resistance and thermal conductivity, were experimentally evaluated, using the Alambeta instrument. The study of the obtained results established the fabrics of non-circular cross-sections as against circular ones, and increase in the linear density results in higher thermal resistance, lower thermal conductivity and lower thermal absorptivity. Wicking behaviour of fabrics was studied under two conditions–wicking from an infinite liquid reservoir (transverse wicking) and wicking from a finite liquid reservoir (single drop wicking into the fabrics). Increase in fibre linear density enhances transplaner wicking but slows down the spreading speed of water drops. Air permeability and moisture vapour permeability are found to be positively correlated with fibre decitex. The role of fibre cross-sectional shapes in influencing mass-flow characteristics is quite considerable. Use of non-circular polyester in place of a circular one augments the wickability of liquid water along with the permeability of air and moisture vapour through the fabrics, revealing their high porosity, which assists air and moisture to propagate. Mixing viscose into polyester brings down the air permeability and moisture vapour transmission rate (MVTR) of fabrics. Results show that moisture absorption of viscose is an important factor in influencing the moisture transport characteristics including both wickability and MVTR of 100% viscose and P/V-blended fabrics.     

Thermal and mechanical characterization of novel basalt woven hybrid structures

This paper presents a study conducted on the thermal and mechanical properties of basalt hybrid and nonhybrid woven structures. While designing fabrics for various industrial textile applications, the knowledge about the mechanical properties is very important. Strength, modulus, and elongation are the most important performance properties of fabrics governing their performance in high-end applications. The thermal properties of the fabrics, i.e. thermal resistance, thermal conductivity were also studied vis-a-vis physiological behavior. In this work, state-of-the-art evaluation techniques are used, which provide reliable nondestructive measurement of thermal conductivity, thermal resistance, water vapor permeability, and air permeability of fabrics. The effect of structure and composition on the above-mentioned properties of such nonstandard fabrics has been investigated in detail. The results of the study show that effect of fiber composition, weave, and geometrical parameters on thermal and mechanical properties is significant in basalt hybrid fabrics.     

Analysis of thermal comfort properties of fabrics for protective applications

Protective clothing protects the body from external influence like heat, chemicals, mechanical hazards, bad weather, etc. by shielding the human body from harsh environmental effects. The maintenance of thermal balance is one of the most important aspects of protective clothing. The study aims to investigate the thermal comfort properties of woven hybrid fabrics produced with high performance core spun yarns. For this purpose, meta-aramid, e-glass, Technora® and Dyneema® fibres were combined using core yarn spinning method in order to enhance the protective performance characteristics. The effects of the core/sheath ratio and type of core materials on the thermal comfort characteristics were investigated and evaluated statistically. The results revealed that, core/sheath ratio, types of core materials have significant effects on thermal comfort characteristics of the fabrics. As the core ratio increases from 19 to 56%, the air permeability of the fabrics increases whereas their thermal conductivity and thermal absorptivity properties decrease. Meta-aramid/E-glass core fabrics can be preferable for protective clothing due to high air permeability and thermal conductivity values.     

Thermo-physiological and comfort properties of Ugandan barkcloth from Ficus natalensis

The United Nations Educational, Scientific and Cultural Organization in 2005 proclaimed that Ugandan barkcloth largely produced from mutuba tree (Ficus natalensis) as a “Masterpiece of the Oral and Intangible Heritage of Humanity”. An exploratory investigation of thermo-physiological and comfort properties of barkcloth, a nonwoven material produced through a series of pummeling processes from mutuba tree in Uganda, is fronted. Barkcloth was extracted from the F. natalensis tree in Nsangwa village, Buyijja parish in Mpigi district, Central Uganda. Thermal conductivity, thermal diffusivity, thermal absorptivity, thermal resistance, fabric thickness, and peak heat flow density were measured using an Alambeta device, whereas a Permetest device was used for the measurement of the moisture vapour permeability and evaporation resistance. The study was carried out under relative humidity of 40% and at a laboratory room temperature of 24°C and the results show that the thermal conductivity is in the range of cotton fabrics rendering barkcloth from F. natalensis, a comfortable fabric. The lower value of thermal absorptivity of barkcloth compared to the value of cotton renders the fabric a warm feeling when in contact with the skin. Barkcloth had a higher moisture vapor permeability compared to cotton and other fabrics, meaning its clothing comfort properties are reasonable.     

Thermo-physiological comfort characteristics of polyester air-jet-textured and cotton-yarn fabrics

Air-jet-textured polyester yarns were produced using two feed yarns differing in filament fineness and number of filaments. By varying the overfed rates of feed yarns and changing their positions in core and effect, five textured yarns were produced. Woven fabrics were prepared using these textured yarns as weft and cotton yarns in warp. To study the effect of air-jet-texturing parameters on the thermo-physiological comfort characteristics of fabric, the woven fabrics were tested for thickness, thermal properties, transverse wicking and air permeability. It is observed that thermal conductivity and resistance of fabrics are not influenced by the texturing parameters/textured yarn structure. These properties are mainly dependent on the entrapped air present in fabrics. Thermal absorptivity is a transient phenomenon of heat flow reflecting that the ‘warm-cool feeling’ effect of fabrics depends on smoothness/roughness of fabric surface. Fabrics with smooth surfaces have higher thermal absorptivity values as they provide a large area of contact with human skin. The roughness of fabrics depends on the number of surface loops and filament fineness. Transverse wicking of fabrics depends on the size, continuity and alignment of the capillaries present in the core of textured yarns.     

Preparation,characterisation of bamboo charcoal particles and the effect of their application on thermo-physiological comfort properties of woven fabrics

Abstract

Bamboo charcoal particles were prepared at micro level and applied on three types of woven fabric, namely 100% cotton, 100% polyester and 65/35 p/c blend. The thermo-physiological comfort properties such as wetting, wicking, water vapour permeability, air permeability and thermal resistance of the control and treated fabrics were investigated to study the effect of bamboo charcoal particles application on these fabrics. The results reveal that the bamboo charcoal treated fabrics show a good improvement in wetting, wicking and water vapour permeability. The charcoal particle finished fabrics also showed a slight decrease in thermal resistance thereby contributing to a corresponding improvement in thermal conductivity with a reduction in air permeability when compared with the control fabrics. The bamboo charcoal treated fabrics showed a good fastness to washing thus exhibiting good durability on the fabrics selected for the study. Also, the charcoal treated fabrics revealed a higher wickability than the control fabrics even after 20 washes.     

The functionality of woven fabric from air-jet yarn from the mixture of CO/PA and CO/PES fibres in the weft direction

The purpose of presented research is to find out the influence of air-jet yarn from the mixture of CO/PA (50/50) and CO/PES (67/33) fibres on functionality of woven fabric in the plain weave.The first part of the study is directed to the mechanical and physical properties of air-jet yarns (16.7 tex) from CO/PA and CO/PES fibres, while the second part of the study focuses on permeability properties of fabrics with air-jet yarns in the weft. The results show that air-jet yarn in the weft direction influences on the water vapor transmission and thermal conduction increase and air permeability decrease.Incorporation of air-jet yarn in the weft direction also improves breaking extension level.The results of presented research also show that the incorporation of air-jet yarn in the weft has statistical important influence on thermal conduction, water-vapor and air permeability changes.     

Thermophysiological comfort properties of selected knitted fabrics and design of T-shirts

Thermal comfort is one of the most important components of comfort which shows physiological, psychological, and physical harmony between human body and environment. The heat and moisture transfer capacity of fabric from skin to environment affects the thermal comfort of garments. The transfer capacity depends on the characteristic features of raw materials and fabric structural properties. In this study, it is aimed to determine the advantages of knitted fabric types, taking into account the environmental condition and activity level by measuring the thermal comfort properties such as air permeability, wicking, moisture management, thermal and water vapor resistances. Two knitted structures composed of tuck and float combinations and six raw materials were chosen for the fabrics produced. According to the measurement results, the polyester and cotton/Coolmax fabrics with float stitches have had good liquid moisture transport properties. Besides, high air permeability and low water vapor resistance have been obtained in viscose and Tencel LF fabrics with tuck stitches. On the basis of the results obtained in this investigation, and taking into consideration thermal behavior of human body, four women’s and five men’s T-shirts are designed. These T-shirt designs may be helpful for further approaches on the optimization of thermal comfort for sports activities in hot environment.     

Effect of blend proportion on thermal behaviour of bamboo knitted fabrics

This study presents the thermal comfort properties of single jersey knitted fabric structures made from cotton, regenerated bamboo and cotton–bamboo blended yarns. Cotton, bamboo fibre and blends of the two fibres (100% cotton, 100% bamboo, 50:50 cotton:bamboo, 67:33 cotton:bamboo, 33:67 cotton:bamboo) were spun into yarns of identical linear density (20?tex). Each of the yarns so produced was converted to single jersey knitted fabrics with loose, medium and tight structures. The thermal conductivity of the fabrics was generally found to decrease with increase in the proportion of bamboo fibre. The relative water vapour permeability and air permeability of the fabrics were observed to increase with increase in bamboo fibre content. Statistical analysis also indicates that the results are significant for air permeability, thermal resistance, thermal conductivity and relative water vapour permeability of the fabrics.     

Stab resistance and thermophysiological comfort properties of boron carbide coated aramid and ballistic nylon fabrics

This research presents the stab resistance and thermo-physiological comfort properties of the fabrics prepared from high-performance fibres of aramid (i.e. Kevlar®) and ballistic nylon. The fabric samples were coated with boron carbide to improve the stab resistance properties. The quasistatic stab tests were performed using NIJ 0115.00 standard knife (P1) on the Instron tensile testing machine. The thermo-physiological comfort properties of the fabric samples were evaluated by measuring the air permeability, water-vapour resistance and thermal resistance. It was observed that the application of the coating significantly increased the stab resistance properties of the fabrics. Furthermore, the air permeability was significantly reduced; whereas, the water-vapour resistance and thermal resistance were significantly increased with the application of coating. Hence, the coated fabrics will have to compromise the comfort aspects to achieve the desired protection level, which is the prime requirement for the stab resistant textile materials.     

灰色理论在麻织物热湿舒适性研究中的应用

利用灰色理论评价麻织物的热湿舒适性,通过测试不同规格麻织物的传热、透气、导湿和吸湿性能,用灰色关联度分析法与蚕丝织物各热湿性能指标构成的参考数列进行比较,排出了夏季服用麻织物热湿舒适性能的优劣次序,为热湿舒适性能的研究提供了理论依据。实验证明:在高湿与低湿状态下,厚度和总紧度对织物的透湿性能产生的影响是不同的;在低湿条件下,紧度产生的影响效果比厚度大,而在高湿条件下,厚度产生的影响因素占据主导地位。     

A study on thermal properties of single-jersey knitted fabrics produced from ring and compact folded yarns

This paper presents a study on the thermal properties of single-jersey knitted fabrics manufactured using ring, compact and ring/compact folded yarns. The variations in thermal properties depending on the yarn twist and traveller weight of folded yarn single-jersey knits were discussed. It was found that the thermal resistance of knitted fabrics generally increases as the traveller weight decreases, and also water vapour permeability reduces as the traveller weight decreases. The water vapour permeability and air permeability of knitted fabrics increase as the twist increases. The thermal conductivity of knitted fabrics decreases as the twist increases. The air permeability and water vapour permeability values were higher for compact folded yarn fabrics as compared to those values of ring and ring/compact folded yarn fabrics. It is observed that yarn twist and traveller weight have affected different thermal properties of single-jersey folded yarn fabrics.     

竹／棉混纺机织物透湿性能与透气性能的分析

本文对7种不同混纺比的竹／棉平纹机织物的透湿性及透气性的性能进行测试，通过一元线性回归分析得到竹含量、透湿性和透气性三者之间的函数关系，从而给予开发竹棉混纺织物提供了一定的理论依据。     

纬编间隔床品面料的结构及性能分析

采用3.3 tex涤纶单丝为间隔纱,8.3 tex涤纶和2.2 tex氨纶交织为表层,制备4种不同密度、厚度及间隔纱连接方式的纬编间隔织物。分析织物组织结构和编织工艺,并测试力学性能和热湿舒适性能,分析面料厚度、密度与各项性能关系,用数学模糊分析法对面料进行综合分析。结果表明,间隔纱连接方式对面料拉伸断裂性和顶破性有一定影响,对透气透湿性无明显影响;厚度、密度较小且间隔纱交叉连接的织物综合性能最好;选择床垫面料时考虑厚度、密度及间隔纱连接方式对面料性能影响。     

聚乙烯针织物的热湿舒适性能

为研究织物结构参数对聚乙烯针织物热湿舒适性能的影响,选取3种规格的聚乙烯长丝织成双罗纹针织物,并选用涤纶、凉感涤纶长丝制备相同结构双罗纹织物作为对比试样,研究构成织物的原料种类、未充满系数、捻度对织物孔隙率、透气性、导热及导湿性能的影响。结果表明:在织物结构相同的情况下,构成织物的原料、未充满系数与织物透气、导湿、导热等热湿舒适性能显著相关;纱线捻度与织物的导热及导湿性能显著相关;与涤纶、凉感涤纶织物相比,聚乙烯长丝表面存在沟壑,结晶度、取向度较高,其织物具有优良的透气、导湿和导热性能,是制备凉爽舒适功能纺织品良好原材料。     

Coolmax纤维含量对交织物舒适性能的影响

对5种Coolmax／棉交织织物的吸水性、透湿性、透气性进行了测试,建立了Coolmax纤维含量与织物经向、纬向芯吸高度,透湿量、透气率的回归方程。结果表明随着纬纱中Coolmax纤维含量的增加,Coolmax／棉交织织物的吸水性、透湿性和透气性越好。