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.     

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.     

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 improved breathability of polyurethane coated cotton fabric via micro-cracking

Polyurethane (PU) coating became popular in the last decades to achieve water resistance garment fabrics with enhanced visual properties. But reduced breathability of coated fabric is a setback for clothing industry. This paper represents a facile method of enhancing breathability (air and water vapor permeability) of PU coated fabrics which may be so-called micro-cracking in relevant solvent bath differed in solvent bath, concentration, and duration time. The samples were subjected to air permeability, water vapor permeability, water resistance, and tensile strength measurements and the results were also statistically analyzed. The study showed that the proposed process increased water vapor and air permeability of coated but the permeability values were still significantly lower than that of uncoated sample. This result is also verified through water resistance measurements and; tensile strength of the samples were affected at minimum after micro-cracking.     

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.     

Evaluation and improvement of thermo-physiological comfort properties of firefighters’ protective clothing containing super absorbent materials

In this research, super absorbent materials were incorporated into the internal layer of the firefighters’ protective clothing with the aim of increasing absorption of sweat to improve the thermo-physiological comfort properties. The performance properties were evaluated following the standard test methods (ISO 6942:2002 and ISO 9151: 1995(E)) and the thermo-physiological comfort-related properties were evaluated by measuring the transport properties such as air permeability, water sorption and evaporation, thermal resistance and water vapour resistance of the fabric assemblies with super absorbent materials. The results indicated that it is possible to improve the comfort properties of the protective clothing by the incorporation of super absorbent materials into the internal layer. The use of super absorbent materials is likely to help in the absorption of sweat in higher amount and keeping the skin and internal microclimate dry, which in turn improves the comfort level. The performance properties of all the combinations satisfied the requirements for firefighter’s clothing as mentioned in AS/NZS 4967-2009.     

Study on thermal and evaporative resistances of multilayered fabric ensembles

The present work deals with the study on thermal and evaporative resistance of multilayered fabric ensembles meant for cold weather applications. Three-layered structure is used to study the thermal comfort properties. Knitted fabric and polytetrafluoroethylene coated fabrics were used in inner and outer layer, respectively. Needle punched fabrics produced from polyester fibre were used in middle layer. Fifteen different non-woven fabrics were produced according to Box and Behnken experimental design for three variables and three levels by varying mass per unit area, punch density and depth of needle penetration. The produced fabrics were evaluated for thermal and evaporative resistances with and without inner and outer layer fabrics. Thickness, air permeability, bulk density and porosity of the needle punched fabrics were studied. The properties of the fabrics were analyzed for statistical significance by using ‘Design-Expert’ statistical software. Artificial neural network model was developed to predict the properties of fabrics and validation of model was done with the testing data-set. The performance of prediction was evaluated by mean square error, mean absolute error percentage and correlation coefficient. It was concluded that the predicted properties of fabric correlated well with the experimental results.     

Electrical conductivity and physiological comfort of silver coated cotton fabrics

The objective of present study was to develop multifunctional and wearable electrically conductive fabrics with acceptable comfort properties by in-situ deposition of silver particles. The effect of silver nitrate concentration and number of dips was investigated for change in electrical conductivity, EMI shielding, and antimicrobial properties of coated fabrics. The dynamic light scattering and SEM analysis were employed to study the morphology of deposited silver particles. The EMI shielding was found to increase with increase in concentration of silver particles. Later, the comfort and mechanical properties were studied. No significant decrease in air permeability and water vapor permeability was observed due to partial coverage of fabric pores by coating of silver particles. Moreover, the coated fabrics also showed promising behavior toward antimicrobial properties. When the durability of coated fabrics was examined against washing, the application of binder provided good retention of silver particles without loss of electrical conductivity of coated fabrics.     

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.     

Investigating the effect of material and weave design on comfort properties of bilayer-woven fabrics

The paper focuses on the development of a bilayer-woven fabric and investigating the effect of weave design and material type on its comfort properties. Face layer was plain woven with cotton yarn, while two different weave designs (2/2 and 3/1 twill) and four different materials (cotton, polyester, micropolyester and nylon) were used for the back layer. The comfort properties of fabric, including air permeability (AP), thermal resistance, water vapour resistance and overall moisture management capacity, were determined. It was found that both the layers of fabric as a whole contribute to the comfort properties of bilayer fabric. The highest AP was exhibited by fabrics having both layers of cotton, while 3/1 twill samples have a lower value of thermal resistance as compared to the 2/2 twill samples. The results further showed that micro polyester woven in 3/1 twill weave exhibits better comfort properties.     

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.     

Thermal and water vapor transmission through porous warp knitted 3D spacer fabrics for car upholstery applications

This paper deals with water vapor transmission and thermal properties of various warp knitted spacer fabrics. In this work, thermal and water vapor permeability of different spacer fabrics have been evaluated by varying the structure, areal density, thickness, type of raw materials, etc. The air permeability and water vapor transmission of the fabrics were measured using the Textest FX-3300 air permeability tester and PERMETEST. The thermal behavior of fabrics was evaluated by Alambeta instrument. Analysis of Variance (ANOVA) was performed using new statistical software in order to compare the influence of different fabric parameters on thermo-physiological 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 thermal conductivity in spacer fabrics. The parameters which mainly influence the water vapor permeability of these fabrics are porosity, density, and thickness. The empirical model for thermal conductivity calculation shows very high accuracy when compared with experimental results. The statistical model for spacer fabrics also predicts the thermo-physiological properties with very high accuracy. These findings are important requirements for further designing of spacer fabrics for car seats and back supports.     

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.     

Establishing thermal comfort: characterization of selected performance and physical properties of fabrics used in hospital operating room uniforms

The purpose of this research was to characterize selected thermal properties of clothing fabrics available to operating room (OR) workers at the University of Alberta Hospital and to relate the thermal properties to fabric structural characteristics. In this study, we measured the thermal resistance and air permeability of fabrics obtained from surgical gowns, scrubs and warm-up jackets currently in use in ORs in a specific hospital. The results showed that the fabrics from which the surgical gowns were made provide the highest thermal insulation with lowest air permeability, while the warm-up jackets’ fabrics had the greatest air permeability with low thermal insulation values. The clothing options available to workers in the OR fall well below the predicted clothing insulation values for thermal comfort. For workers in the OR, such as anaesthesiologists, who are predominantly sedentary throughout their work shift, the lack of thermally insulating clothing options has consequences for their overall thermal comfort. This study comprises part of a larger ongoing study investigating improving the OR workers thermal comfort through clothing.     

聚碳氟烃纳米纤维膜在纺织品防钻绒应用的可行性

在羽绒制品中,防钻绒性能、透气性与耐水洗性能均满足检测标准要求的面料很少,导致羽绒面料品种单一,羽绒制品多样性也受到限制。通过在羽绒面料上复合一层由聚碳氟烃纳米纤维技术制成的防绒膜,研究面料覆膜前后防钻绒与透气性、覆膜面料水洗前后防钻绒与透气性的变化。结果表明:复合了碳氟烃聚合物纳米纤维材料制成的防绒膜,防钻绒性明显得到提升,透气性与耐水性能仍能满足检测标准的要求,有效解决了羽绒面料品种单一的问题。     

Study on effect of blend ratio on thermal comfort properties of cotton/nylon-blended fabrics with high-performance Kermel fibre

This study presents the thermal comfort properties of woven fabrics made of Kermel, cotton/nylon and cotton/nylon /Kermel-blended yarns. Our aim in this study is to combine the high comfort properties of cotton/nylon fibres with high thermal protective properties of Kermel fibre in different woven fabrics. Thus, Kermel (100%), cotton/nylon (50:50) and four blends of the 50% cotton fibres with nylon and Kermel (40:10, 30:20, 20:30 and 10:40) were spun on a ring-spinning frame and twisted into two-folded yarns with the same yarn count of 30/2(Ne) and twist level of 560 TPM. Using the produced yarns, woven fabrics with identical characteristic and structure were also produced. Then, the thermal comfort and physical properties of fabrics were studied in terms of fabric porosity, thermal resistance, thermal conductivity, water vapour resistance and air permeability. The results show that the porosity, air permeability and thermal resistance increase with Kermel fibre blend ratio. Conversely, the water vapour resistance decreases with increase of Kermel fibre blend ratio up to 40%, while 100% Kermel-woven fabric exhibits a higher water vapour resistance value. Nevertheless, the thermal conductivity of cotton/nylon-blended Kermel woven fabric is unchanged with increase of Kermel fibre blend ratio up to 40%, whereas at 100% Kermel fibre blend ratio, the lowest thermal conductivity is obtained. The obtained results implied that woven fabric produced from cotton/nylon (50/10) blended with 40% Kermel fibre resulted in proper thermal comfort properties.     

An investigation of thermal comfort properties of Abaya woven fabrics

Abaya is a traditional Muslim woman’s outer garment. It is black in colour, and must be worn over the normal day-to-day clothing according to Islamic law. It is mandatory to wear Abaya in Arabian Gulf countries irrespective of the outside environmental temperature, which can be up to 50°C. Having many layers of clothing including Abaya makes it extremely uncomfortable for the wearer in a hot environment. Thermal comfort performance is, therefore, essential for fabrics used for Abaya. This study investigated some commercially available woven Abaya fabrics for thermal resistance, air permeability, thermal comfort, vapour resistance and fabric structural and surface properties. The results indicated that the Abaya fabrics with different weave structures, fibre composition and fabric weight have greater influence on the fabric thermal comfort performance.     

改性聚丙烯酸类纤维吸湿发热机织物的开发

为研究吸湿发热保暖机织物的热湿舒适性,开发了6种不同结构的改性聚丙烯酸类纤维吸湿发热机织物。通过热湿舒适相关性能测试与分析,得出不同机织物结构参数对透气性、热阻、芯吸高度、液态水分管理以及吸湿发热性能的影响规律,为设计出兼具吸湿发热和导湿排汗性能的热湿舒适机织物提供参考。经测试发现:蜂巢组织能明显改善织物的保暖性和透气性,且织物由内层向外层形成回潮率递增的梯度结构,对水分管理和提高单向导湿性能有积极作用,三层蜂巢组织在提升织物吸湿发热性能上具有一定潜力。     

改性聚丙烯酸类纤维吸湿发热机织物的开发

为研究吸湿发热保暖机织物的热湿舒适性,开发了6种不同结构的改性聚丙烯酸类纤维吸湿发热机织物。通过热湿舒适相关性能测试与分析,得出不同机织物结构参数对透气性、热阻、芯吸高度、液态水分管理以及吸湿发热性能的影响规律,为设计出兼具吸湿发热和导湿排汗性能的热湿舒适机织物提供参考。经测试发现:蜂巢组织能明显改善织物的保暖性和透气性,且织物由内层向外层形成回潮率递增的梯度结构,对水分管理和提高单向导湿性能有积极作用,三层蜂巢组织在提升织物吸湿发热性能上具有一定潜力。     

Comparison of thermal comfort properties of single jersey fabrics produced by hollow yarns with different hollowness ratio

In this study, the thermal comfort properties of single jersey fabrics produced by conventional and hollow cotton yarns with different hollowness ratio have been investigated and compared. For this purpose, thermal conductivity, thermal resistance, thermal absorptivity, air permeability and water vapour permeability of core spun, hollow and conventional yarn fabrics were measured and evaluated statistically. It was observed that thermal comfort properties of single jersey fabrics were affected by the yarn structure and the fibre distribution within the yarn. The results showed that hollow yarn fabrics had better thermal comfort properties than that of conventional yarn fabrics. In hollow yarns, as the hollowness ratio increases, air permeability and thermal conductivity of single jersey fabrics decrease but thermal resistance, thermal absorptivity and water vapour permeability increase. Statistical analysis also indicated that the differences between properties of hollow yarn fabrics and conventional yarn fabrics were significant. Furthermore, the yarn hollowness ratio significantly affects thermal comfort properties of single jersey fabrics.