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Comfort is the prime need in clothing. It is affected by the properties of fibers, yarns, and fabrics. A good understanding of these factors is essential in the design and conception of functional clothes. Fabric design serves as a manufacturing tool to meet several end-use requirements. The construction specifications and design of knitted fabrics greatly influence the comfort level of the end-use garment. This study aims to investigate the effect of the knitting stitch type and the dyeing process on the clothing comfort of knitted fabrics. For this purpose, five structures were prepared by combining plain, float and tuck stitches: plain jersey, cross miss 1 × 1, single cross tuck, weft lock knit and Lacoste. Then, yellow, and black dyeing were applied. The investigated wear comfort properties were the drying time, the air permeability and the relative water vapor permeability. Tests were conducted on the finished and on domestically washed fabrics. The data obtained were statistically evaluated with Pearson correlation, paired t -test, analysis of variance analysis and the Tukey test. The results showed that tucked fabrics have the longest drying time combined with the lowest air and water vapor permeability. Black variants showed better drying behavior and higher water vapor permeability. Analysis of variance results showed that the structure has a significant effect on clothing comfort. However, the dyeing process exerts a significant influence only on the drying time and the relative water vapor permeability. The paired t -test results indicate that the domestic washing cycles significantly change the drying time and the air permeability of knitted fabrics. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic has highlighted environmental and supply issues related to single-use protective masks for both the general public and some healthcare workers. Reusable fabrics are an interesting alternative to disposable nonwovens and offer a prospect of protection in other fields such as against fine particles in urban areas. In this paper, the behavior of 22 woven fabrics regarding air permeability, simulating breathability through the material, and filtration against 3 µm diameter particles is investigated. First, basic laws are verified between the performance of a single layer of fabrics and that of a stack. A relationship is established between air permeability and filtration efficiency, allowing one to be calculated when the other is known. Second, the influence of parameters defined at various scales of the structure (fibers, yarns and fabrics) is analyzed. The most sensitive structural parameters that can be considered as predictors are then identified and used in a model allowing the calculation of air permeability. In this model two levels of porosity are taken into account: a macroscopic porosity at the scale of the woven structure and a microscopic porosity at the scale of the thread. The model proposed in this study offers a convenient method to design an effective filter from data easily measurable during manufacturing. [ABSTRACT FROM AUTHOR]

Electromagnetic interference shielding clothing has been developed for people who is sensitive to electromagnetic radiation or workers working under extremely high electromagnetic radiation circumstances. The challenge was developing the fabric with good washability, durability, and air permeability. After three machine washing cycles, the electromagnetic interference shielding effectiveness can drop more than 99% for untreated copper-coated fabric. In this research, the chlorinated poly-para-xylylene (parylene C) encapsulating technology was used to protect the fiber's copper particles. The result shows that the treated sample's washing ability will significantly improve after processing 15 g parylene-C on the copper-coated fabrics. The electromagnetic interference shielding effectiveness can remain at 39.93 dB and 25 dB on average from 30 MHz to 3 GHz after 10 hand washing cycles and 10 machine washing cycles, respectively. The air permeability remains around 1043.6 mm/s for a 15 g parylene-C encapsulated sample. The chemical resistance property was also improved significantly after encapsulation of 15 g parylene-C. For the 15 g parylene-C encapsulated samples, there is less than 3% loss of electromagnetic interference shielding effectiveness after 8 h of immersing into pH = 2 and pH = 12 solution. The overall structure of the 15 g parylene-C encapsulated fabric remains intact after 6000 abrasion cycles. The study presents an effective method for fabricating highly durable, comfortable electromagnetic interference shielding fabric, guaranteeing reliability for technical clothing applications and showing great potential for further development. [ABSTRACT FROM AUTHOR]

The main goal of this research was to determine the influence of the inner layer thickness and tightness, which depends on the length of the float determined by the float step and number of floats in the pattern repeat, on the thermal insulation and air permeability of the multilayered weft-knitted fabric. For this reason, weft-knitted spacer fabrics were produced by using woolen yarns for the outer layers and polyester filament yarn for the inner layer, with the number of floats in the inner layer varying between two and 20. Results from this research showed that the consequent increase in thickness and tightness of the spacer fabric's inner layer has unequal effect on the thermal insulation and air permeability. Therefore, similar thermal insulation can be achieved by having significantly higher air permeability. This is especially evident over a long period of time. [ABSTRACT FROM AUTHOR]

The market for sports-abaya in Saudi Arabia is growing due to an increasing participation rate of Islamic women in fitness and sports activities. As mandated by religious law, an abaya must be worn over daily clothes or sportswear by women in order to hide their body contour. The additional layer of the abaya will affect thermal comfort and performance of the wearer. Hence, a sports-abaya needs to be specifically designed to facilitate thermal comfort. This necessitates the selection and evaluation of fabrics appropriate for use in the production of sports-abaya. This study compared two fabrics (100% cotton knit and 100% polyester woven) for their air permeability, thermal resistance and evaporative resistance. The fabrics were then incorporated as sole variable into two models of sports-abaya. The thermal properties of these abayas were evaluated using a female thermal manikin in both standing and walking positions. Comparison was made with the results of a traditional abaya. The research work revealed that polyester woven fabric has a higher air permeability (44.9 mL/cm2/s) than cotton knitted fabric (24.1 mL/cm2/s). The vapor resistance of polyester fabric was lower than cotton fabric and their thermal resistant did not show any significant difference. Consequently, thermal manikin evaluation showed results favoring sports-abaya containing polyester fabric in both standing and walking positions. Furthermore, the thermal resistant and vapor resistant values of sports-abayas were lower compared with those of the traditional abaya. This leads to the conclusion that the newly designed sports-abaya containing 100% polyester woven fabric provides better thermal comfort than traditional abaya and sports-abaya containing 100% cotton fabric. [ABSTRACT FROM AUTHOR]

Air penetration behavior plays a vital role in the performance of fibrous material in various industrial applications. Two parameters, the permeability coefficient and airflow resistivity, can describe the air penetration behavior of fibrous material. FX 3300 Textech Tester III and AFD300 AcoustiFlow devices were used to respectively characterize the permeability coefficient and airflow resistivity of nonwoven materials. Nonwoven samples were compressed due to the load from the test head of the FX 3300. Finite element analysis along with the mathematical method were implemented to recover the airflow permeability of samples at the uncompressed state. The effects of pressure drop on the airflow velocity and permeability coefficient were analyzed by the Ergun-type model. The determination of airflow resistivity based on the permeability coefficient is carried out via two approaches, that is, the direct method and the extrapolation method. The results show that the airflow velocity is not linearly related to the pressure drop, which differs from Darcy's law. This non-linear relation is mainly attributed to the influence of frictional loss. By comparing the relative error between assessed and measured airflow resistivity, most of the assessed values of the compressed samples are overestimated. The results also suggest that the direct and extrapolation methods are applicable to assess airflow resistivity on an airflow velocity (or air permeability) test device. Moreover, the Ergun-type model is also applicable to determine the permeability coefficient and airflow resistivity of nonwoven materials. [ABSTRACT FROM AUTHOR]

The research aim was to analyse the changes in the air permeability, waterproofness, surface, mechanical and thermal properties of the polyamide 6.6 fabric with a polyurethane coating before and after 1, 5, and 10 washes in the same conditions using specialized (V1) and universal (V2) laundry detergent. A new approach based on SEM and DSC techniques and assessment of surface free energy combined with standard methods was proposed to explain the nature of observed changes in waterproof and breathable material after washing treatment. SEM analysis indicated that after 10 washes the porosity of the polyurethane coating increased from 8.94% to 14.56% and 18.75% for V1 and V2, respectively. The air permeability increased from 0.747 mm/s for the reference sample to 0.766 mm/s and 0.774 mm/s after 10 washes for V1 and V2, respectively. The waterproofness of the reference sample of 992 mbar decreased with the increasing number of washes to 246 mbar and 122 mbar for V1 and V2, respectively. After 10 washes the surface free energy (γS) decreased by 18.8% and 24.3% for V1 and V2, respectively. The average tensile strength amounted to 833 N and decreased by 13.5% for V1 and by 20% for V2 after 10 washes. The glass transition temperature of the reference fabric was 47.6°C. After 10 washes it increased by 7.2°C and 8.8°C for V1 and V2, respectively. The temperatures of thermal degradation increased by 24.6°C and 22.2°C and the heat of thermal decomposition decreased by 23.6% and 15.8% after 10 washes for V1 and V2, respectively. [ABSTRACT FROM AUTHOR]

The number of filaments in yarn cross-section, weave density, and weave type are considered the most important factors that affect the property of air permeability of multifilament woven fabrics. Microfilament yarns significantly affect the air permeability property of this type of fabric because of the low porosity between the filaments. This study deals with the development of a fuzzy logic model for predicting the air permeability of multifilament polyester woven fabrics produced from conventional and microfilament yarns. The polyester multifilament yarns used in this study were produced with three different microfilament fineness and two conventional filament fineness levels. The woven fabric samples used in this study were obtained in three weave types: plain, twill, and satin, and with five different weave densities. In accordance with the experimental test results, both regression analysis and fuzzy logic system were built. The air permeability results generated from the developed fuzzy model and the regression equations were compared with the experimental values. Satisfactory and accurate prediction results were obtained with the developed fuzzy logic model. The mean absolute error of the fuzzy model and regression analysis were found to be 2.32%, 12.59%, respectively. Therefore, it was confirmed that the fuzzy model was superior in predicting air permeability. [ABSTRACT FROM AUTHOR]

This article presents an investigation on effects of heat treatments in the range 400–700℃ on morphology, fractal dimension, pore size distribution, and air permeability of superfine glass fiber felts. During the heat treatments, the released residual stress, thermal decomposition, and thermal contraction make fibers bend to different degrees, corresponding with different fractal dimensions. The felt pores are formed by the random interlacing of fibers, varying with the different bending degree of fibers, which results in an influence on the air permeability of the felt. The results show that there was no visible change in the morphology of the heated felt at 400–550℃. However, the treatment at 600℃ could cause the breakage of some fibers, and above 650℃ the damage of felts. The fractal dimension of heated felt decreased at 400 and 450℃, but then increased above 500℃. The lowest fractal dimension was 1.8827 at 450℃, and the highest was 1.9666 at 600℃. Besides, the pores tend to distribute in a smaller size and a narrower scale under high temperatures, resulting in a decrease in the air permeability. However, the air permeability had the same variation trend with fractal dimension at 400 and 450℃, but opposite above 500℃. The relationship among them was verified by comparing the experimental and theoretical results. At 600℃, the mean pore size and the air permeability reduced by 16% and 31%, respectively. [ABSTRACT FROM AUTHOR]

The main aim of the study is to present a new innovative method designed by the author of non-destructive, accurate and morphometrical identification of fabric structural parameters, individual inter-thread pores (ITPs) in particular. The description parameters and fabric structure assessment methodology with the use of digital image analysis with author's copyrighted MagFABRIC software were created specifically for this analysis. The ITP parameters were described in three aspects: size, shape and location in the fabric structure. The study was conducted on two groups of fabrics: plain and twill weave. The need for a bimodal analysis of the fabric structure parameters was indicated, as it allowed for the structure differences identification in the test fabrics. The analysis results were compared to the air permeability test. The developed methodology is relevant to specialized fabrics (e.g. barrier fabrics, industrial filters and any other fabric where the ITP area is an important parameter). [ABSTRACT FROM AUTHOR]

In this paper, a super-hydrophobic cotton fabric was fabricated by low-pressure plasma-enhanced chemical vapor enhanced deposition (LP-PECVD) with lauryl methacrylate (LMA) as the functional monomer. Scanning electron microscopy (SEM), atomic force microscope (AFM) and X-ray photoelectron spectroscopy were used to analyze the changes of surface morphology and chemical composition of the cotton fabrics surface, respectively. A randomly wrinkled morphology was exhibited by SEM and AFM. The combination of the low surface energy film of LMA and micro-nano-scale structure resulted in the super-hydrophobicity of modified cotton fabrics. The reactive species in LMA/Ar plasma were studied by optical emission spectroscopy, and based on the results of the test, the reaction principle in the plasma reaction chamber was discussed. It was proved that the LMA film is polymerized by chemical bonds on the surface of cotton fibers. The water repellency, washing stability, water-vapor transmission, air permeability and tensile property of fabrics were also discussed. We found that a washing-stable and breathable super-hydrophobic cotton fabric can be achieved after treatment without decreasing the tensile property. [ABSTRACT FROM AUTHOR]

In this study, the effects of physical parameters on the acoustic absorption properties of woven fabrics were studied. The acoustic absorption properties of 24 kinds of woven fabrics with different structural parameters were measured and analyzed. Multiple linear regression models have been established to characterize the relationship between acoustic behavior and various physical parameters. It has been found that the acoustic absorption properties were mainly determined by the perforation ratio and air permeability. The decrease in perforation ratio and air permeability results in an increase of acoustic absorption properties of woven fabrics. Furthermore, three woven fabrics were used to validate the proposed multiple regression models. The established models could well predict the acoustic absorption properties of woven fabrics where the correlation coefficient is higher than 0.77 with air gaps of 1, 2, and 3 cm, respectively. [ABSTRACT FROM AUTHOR]

In this study, 32 different electro-conductive fabrics and seven different non-conductive fabrics were taken for an analysis of their electromagnetic shielding ability, electrical resistivity and air permeability. According to the present state of development of electromagnetic shielding textile structures, a diverse set of samples was selected, including stainless steel, copper, silver, aluminum, carbon and polypyrrole as a conductive component. The ASTM D4935 coaxial transmission line method was used to study the electromagnetic shielding and the ASTM D257 ring electrode method was used to evaluate the surface and volume electrical resistivity of all the samples. Air permeability was considered as an additional important parameter for the production of electromagnetic radiation protective fabrics designed for technical or clothing applications. It was confirmed that textile structures made of conventional textile fibers are transparent to an electromagnetic field. The electromagnetic shielding effectiveness of non-conductive samples is less than 0.2 dB regardless of material composition. On the other hand, the electromagnetic shielding effectiveness of electro-conductive samples containing different content and types of conductive component ranges from 1 to 79 dB at the high-frequency range, whereas the woven sample containing 75 wt% of staple metal fiber provides excellent shielding ability together with high air permeability. It was confirmed that, in particular, the surface resistivity can be used to predict the electromagnetic shielding ability of fabric samples due to a strong inverse relationship between these two parameters. [ABSTRACT FROM AUTHOR]

Air permeability is a very important property influencing the performance of clothing comfort and technical textiles particularly in applications for protective products, including airbags, parachutes, and tents. Several analytical models for predicting air permeability have been made by considering porosity and pore diameter or porous area. However, the connection between fabric structure and air permeability with analytical models has not been well reported as yet.In this work, the diameter of cotton yarn was predicted by considering yarn count, twist, and packing density. Subsequently, the pore area and equivalent pore diameter of fabric were predicted after finding the warp and the weft densities of fabric. The predicted values had very good agreement with the experimental results in yarn diameter and other structural parameters of fabric. The air permeability of fabrics was measured and several well-known analytical models for predicting air permeability were compared. The results revealed that the Hagen–Poiseuille equation had much better prediction than other models and also had good agreement with the experimental results, especially when it was applied for tight fabrics at low pressure drop (≤60 Pa). The Hagen–Poiseuille equation could be improved by considering the Reynolds number, interfiber interstices, and the deformation of pores under higher pressure drop. [ABSTRACT FROM AUTHOR]

This paper deals with performance properties related to human thermo-physiological comfort of three-layer textile systems used for the production of outerwear for cold protection. The transfer of heat and fluids through the compound single layers (woven and non-woven) is investigated and compared to the heat and mass transfer of the systems for clothing. Six characteristics are measured for both single layers and systems of layers: thermal resistance, air permeability, water vapor resistance, relative water vapor permeability, the accumulative one-way transport index and overall moisture management capacity. For each of the characteristics, regression analysis is applied to prove or reject the proposed mathematical dependencies between the transfer abilities of the single layers and the respective systems. The results obtained showed that the fluid transfer abilities of the single layers applied in clothing for cold protection strongly affect the fluid transfer ability of the system of layers, while the heat transfer of the system is dominated by the heat transfer ability of the thermo-insulating layer. The proposed approach for assessment of the transfer processes through a system of layers for the production of outerwear for cold protection could be successfully applied in the design of other textile and clothing items, produced by using systems of different textile layers. [ABSTRACT FROM AUTHOR]

This study aims at investigating air permeability in the transversal direction of pairs of woven textiles. Three samples of woven macrostructures with different characteristics are selected for the numerical investigation of 16 two-layer ensembles. Computational fluid dynamics (Reynolds-averaged Navier–Stokes equations) is used for modeling the air permeability, applying the theory of jet-systems: the flow through each of the layers in the ensemble is modeled as an “in-corridor” ordered jet-system. The influence of the order of arrangement of the layers in the ensemble is analyzed, indicating higher air permeability of the ensemble when a tighter structure is placed as a first layer. The effect of the distance between the two woven macrostructures is also analyzed, showing a strong influence on the flow development as well as on the extrema of flow velocities, especially in the drop of the flow velocity in the air gap between the two layers. The analysis made and the results obtained show that the method can be applied for further investigation of ensembles of textile layers. [ABSTRACT FROM AUTHOR]

Permeability and porosity of woolen fabrics are investigated experimentally in this paper. Permeability experiments are conducted in a wind tunnel to the TS 391-EN ISO 9237 standard. Woolen fabric is placed in the test section of the wind tunnel to measure permeability to airproofing . Velocity measurements are made used a hot wire anemometer in the front and rear of the wool. Air permeability is closely related to pore size and distribution. So, it is important to study porosity, in order to classify and determine the right use of woolen fabrics. Many methods are used to estimate porosity. In this study, the theoretical model is used for determination of porosity values, and the influence on porosity of various fabric parameters was investigated. Depending on the permeability, weft and warp density, weight, fabric thickness and porosity relationship are investigated. The results are presented as graphs. [ABSTRACT FROM AUTHOR]

The aim of the present study was to obtain high-performance materials for heat and flame protective clothing. Therefore, hybrid membranes were prepared using Kevlar as support and aromatic polyimide nanofibers as a protective coating. The exceptional performances of the prepared membranes were highlighted by selected indicators: high thermal stability, fire resistance and improvement in air permeability without modifying drastically the water vapor transmission rate properties. Attenuated total reflectance Fourier transform infrared and 1H nuclear magnetic resonance spectroscopy were employed to confirm polyimide formation. The ability of polyimide to form fibers was investigated by rheological measurements and scanning electron microscopy, respectively. Thermal degradation was studied using thermogravimetric analysis and a microscale combustion calorimeter. The transport properties of the materials were examined by air permeability, water vapor transmission rate and water resistance. It was shown that transport properties of the modified Kevlar membranes could be controlled by varying the spinning time of polyimide solution. Moreover, by annealing the modified Kevlar weavings at 260℃, the structural integrity and transport properties were not affected, whereas a higher resistance to water was found. [ABSTRACT FROM AUTHOR]

Convective heat transfer plays a very important role in thermal resistance of textiles due to its porous structure, and the thermal resistance of textiles will be quite different when they are investigated under different testing standards and conditions. Nowadays, however, there is still no commercial instrument for evaluating the thermal resistance of textiles under convective heat transfer. Besides, there is no report about the influence of pore structure (pore size and the ratio of a pore’s cross-sectional area to the total cross-sectional area of fabric) on thermal resistance of textiles. Therefore, in this work, one newly designed device has been developed for evaluating the thermal resistance of textiles with different parameters in terms of porosity, pore size and pore cross-sectional area under heat convection. The results showed that with the increase of the pore size and the ratio of pore area to total area of fabric, the air permeability increases and the thermal resistance of fabric decreases; the pore size and the ratio of pore area have more significant influence compared to the influence of porosity; and the thermal resistance decreases with the increase of air permeability. [ABSTRACT FROM AUTHOR]

Through-thickness permeability (TTP) is one primary property of technical textiles used in air-related applications, such as filtration and protection. The TTP depends on the textile geometrical factors and usually varies according to the test conditions. In this article, the effect of low air pressure compression (LPC) on TTP of woven fabric was investigated. Nine woven fabrics were measured for the relationships of LPC and thickness, LPC and fabric in-plane dimensions, air pressure drop (APD) and air velocity, as well as LPC and fabric TTP. A dramatic decrease of woven fabric thickness was found below the APD value of 200 Pa and less decreased thickness was observed with a continued increase of APD. The variation of fabric in-planar dimensions was found to be negligible during LPC. The plot relationship of the APD and measured air velocity was presented in linearity for most fabric samples. The fabric TTP showed a linear proportion to the fabric thickness, indicating the fabric to be more permeable with the increase of thickness. A sensitivity study showed an evident difference between using fabric constant and decreased (LPC) thickness in calculating TTP, disclosing the importance of compression in fabric TTP evaluation. [ABSTRACT FROM AUTHOR]

In this paper, we measured the thermal and moisture management properties of six different types of polyester knitted fabrics that are used in the production of summer cycling clothes. The test samples were selected from the most commonly used fabric structures according to the results of a survey on a cycling team in Bursa. The fabrics were compared to determine which fabrics were more convenient for cyclists. Thus, we carried out objective fabric tests to determine the thermal resistance, water vapor resistance, air permeability and moisture management properties. Good moisture comfort, low water vapor resistance and good moisture management properties were preferred, especially in summer clothes. In the final evaluations of the fabrics, it was found that Type 6 Warp knitted raschel fabric was more convenient for summer cycling clothing because of its good air permeability, low thermal resistance, low water vapor resistance and good moisture management properties. [ABSTRACT FROM PUBLISHER]

The paper presents computational fluid dynamics-based numerical simulation of the through-thickness air permeability of woven structures, applying the theory of jet systems. The flow through the interstices between the warp and weft threads is modeled as an “in-corridor”-ordered jet system, formed by nine jets, issuing from nine pores of the woven structure. Fifteen cases were simulated and three different turbulence models were applied in the simulation: k-ɛ, k-ω and Reynolds stress model. The five simulated woven structures were manufactured and their air permeability was measured experimentally. The performed validation of the numerical results with the experimental values of the air permeability showed very good correlation with the experimental results. The analysis and the verification showed that the method can be applied for further investigation not only of the woven fabrics’ air permeability, but also for investigation of the flow after a textile barrier of a woven type. [ABSTRACT FROM AUTHOR]

An intelligent textile with optimal environmental responses was developed from electrospun nanowebs with controllable pore structures via the spinning conditions. The use of shape memory polyurethane allowed the material’s shape to be retained and recovered through heating. The thickness of the electrospun nanoweb was varied so as to manufacture the membrane with various pore diameters. The samples were evaluated for shape memory performance, air and water vapor permeability.All samples showed shape recoveries of at least 99% and shape retentions of at least 94%. Increasing the thickness, increased the shape retention but slightly reduced the shape recovery. Pore size decreased with increasing thickness, thus decreasing air and water vapor permeability.Stretched nanowebs showed the greatest differences in water vapor permeability at 10°C with 90% RH and at 15°C with 90% RH compared with original nanowebs. [ABSTRACT FROM PUBLISHER]

In this study, the effects of physical parameters on sound absorption properties of nonwoven fabrics were investigated. Eight different nonwoven composites including different fiber types mixed with different ratios were tested. Along with sound absorption properties, thickness, weight per area, and air permeability parameters of the samples were measured. The increase in thickness and the decrease in air permeability results in an increase in sound absorption properties of the material. The samples including 70% cotton and 30% polyester resulted in the best sound absorption coefficient in the mid-to-high frequency ranges. The increase in the amount of fiber per unit area resulted in an increase in sound absorption of the material. Addition of acrylic and polypropylene into a cotton and polyester fiber mixture increased the sound absorption properties of the composite in the low and mid-frequency ranges also. [ABSTRACT FROM PUBLISHER]

Air permeability is one of the important properties which affect the performance of nonwovens used for filtration, insulation and drainage applications. In this study, an analysis on the air permeability of the polyester/viscose blended needle-punched nonwovens has been carried out. In addition, a mixture-process crossed regression model with two mixture components (polyester and viscose blend ratios) and two process variables (fabric mass per unit area and needling density) is developed to analyze the air permeability of polyester/viscose blended needled nonwovens. For this purpose, five different blend ratios of polyester/viscose webs were produced, cross lapped and needled in four different mass per unit areas and three different punching densities. Air permeability of sixty nonwovens was determined by performing standard test method and the data obtained from tests were statistically analyzed with the Design Expert software. In conclusion, blend ratio of polyester-viscose fibers in web, fabric mass per unit area and needling density have major effects on the air permeability of nonwovens and the generated statistical model has given satisfactory predictions about air permeability. [ABSTRACT FROM PUBLISHER]

Air permeability is one of the fundamental textile properties influencing the design of comfortable clothes. In particular, it is very important in the field of technical textiles. Air permeability depends mainly on the fabric structure, which can be described by yarn linear density, type of yarn, warp/weft density and weave.The purpose of our study was to identify a small number of parameters that have the strongest influence on air permeability of cotton fabrics and enable its good prediction. Rather than focusing on the constructional parameters, we decided to include a composite parameter known from the theory of fluids, hydraulic diameter of pores, which treats rectangular-shaped pores as circular ones. In addition to the hydraulic diameter of pores, two other parameters were used for the prediction of air permeability: the number of macro pores and the total porosity of woven fabrics.36 woven fabric samples were produced using nine frequently implemented weave types together with two warp densities (29.3 and 22 ends/cm) and two weft densities (15 and 20 picks/cm), resulting in four different densities of woven fabrics. The yarns had the same linear density and material in warp and weft directions. Air permeability measurements were performed with the Air Permeability tester FX 3300 Labotester III (Textest Instruments) according to the ISO 9237:1995 (E) standard.Principal components analysis revealed that the four investigated plain weave specimens behave differently than the other samples, which might be explained by weave structure. This multivariate statistical method also confirmed the appropriateness of the three selected parameters for air permeability prediction which was done using multiple linear regression. The high adjusted coefficient of determination (R2) value of 0.94 indicates that the model explains variability in the air permeability to a large extent. [ABSTRACT FROM PUBLISHER]

The aim of our work was to establish whether very good to excellent UV (ultraviolet) protective properties of fabrics can be obtained through a suitable fabric construction and yarn colour, at the same time ensuring suitable air permeability. For this purpose, six different fabric structures divided into three groups were employed. The samples were made in blue and red combinations of weft with different sequences and proportions between the upper and lower weave threads. A comparison of different fabric structures and colours was attempted to enable the assessment of the impact of the mentioned parameters on both, UV protective properties and air permeability of fabrics. The analysis comprised the investigation of physical and permeability properties, as well as the colour measurements on twelve different cotton fabrics. The research indicated excellent UV protection (>60) in all samples. UV protection depended on their construction and in a sufficiently closed structure, also on the colour of the used yarn. There was no significant difference between the samples in blue and red. In addition to excellent UV protection, four samples (one double-weft and three double fabrics) also demonstrated very high air permeability, which was 3–5 times higher than in the one-layer sample, which demonstrated the best UV protective properties. The research has shown that fabrics with a very high ultraviolet protective factor value and good air permeability can be made by using a suitable construction and yarn colours that sufficiently absorb UV light; the latter being particularly important for light summer cotton clothes. [ABSTRACT FROM PUBLISHER]

Socks need to perform better in comfort properties than other garments, as less air circulation occurs in socks in shoes than in garments on other parts of the body. In this paper, we studied the comfort properties of socks made from new fibers, such as modal, micro modal, bamboo, soybean, and chitosan. In order to compare their properties with conventional fibers such as cotton and viscose, these fibers were also included in the study. Water vapor transfer, air permeability, wicking, wetting and heat transfer -- properties which are related to comfort -- were evaluated. In order to conduct thermal conductivity measurements, a special experimental setup was designed according to the hot plate method (ISO 8302). The results suggested that the fiber type, together with regain and fabric properties such as thickness, appears to affect some comfort-related properties of the fabrics. It is suggested that for certain end uses, various combinations of fiber blends can be used. [ABSTRACT FROM AUTHOR]

Carbon dioxide (CO2) is becoming a promising alternative to perchloroethylene in dry cleaning. In this work, the effect of CO2 dry cleaning on some physical and mechanical properties of six different pure wool and wool/cashmere fabrics was investigated in order to detect any possible fabric modification. It was found that the CO2 dry cleaning process especially affected the thickness and compressional energy, making the fabrics thicker and fuller. A marked increase in shear hysteresis was detected, while no particular variations in bending and tensile properties or crease pressing performance were noted. Finally, there was a significant decrease in the air permeability of three of the six fabrics involved. [ABSTRACT FROM AUTHOR]

The protection provided by clothing against ultraviolet (UV) radiation has been the subject of considerable recent research. However, a lack of investigations concerned with the influence of yarn properties on UV protection capabilities of fabrics seems to be present. This study investigated the influence of yarn twist and surface geometry on these properties of fabrics. The gray-state plain cotton knitted fabrics were produced from yarn differing in twist level under controlled conditions, so as to obtain as similar as possible construction of the fabrics. These plain knitted (single jersey) fabrics were spectrophotometrically assessed and UV protection factor was calculated. The results obtained indicated that yarn twist to a great extent influenced the UV protection properties of the knitted fabrics through the influence on yarn compactness and surface properties, which in turn influenced the open porosity of the fabric. The results were also interpreted as the consequences of minimal differences between knitted fabrics' construction (different stitch density), which could not be avoided because of the yarn twist differences. [ABSTRACT FROM AUTHOR]

This paper reports an exploratory study on the production and measurement of the air permeability, mechanical properties, pore size distribution and filtration efficiency of different nonwoyen fabrics produced by systematically changing the machine variables to influence the physical parameters of the fabrics. Only flax fiber waste was utilized for this trial, so that the possibility of value addition to a cheap source of raw material could be explored. The changes in air permeability were interpreted in terms of fabric density profile and pore size distribution. The tensile strength, fiber orientation distribution and bond strength between the layers of multi-layered fabrics were investigated. The filtration parameters, such as filtration efficiency, dust holding capacity and pressure drop, were evaluated. Furthermore, the effect of calendering on pore size and filtration properties was evaluated to explore the possibility of fine-tuning the performance of filters. The results in this study showed an overall improvement in all filtration characteristics due to the calendering operation. [ABSTRACT FROM AUTHOR]

Wool fabric was treated with low temperature plasma (LTP) with a non-polymerizing gas, namely oxygen. After the LTP treatment, the properties of the fabric, including low-stress mechanical properties, air permeability and thermal properties, were studied. The low-stress mechanical properties obtained by the means of Kawahata Evaluation System Fabric (KES-F) revealed that the tensile, shearing, bending, compression and surface properties were altered after the LTP treatment. The changes in these properties are believed to he related closely to the interfiber and inter-yarn frictional force induced by the LTP treatment. The decrease in the air permeability of the treated wool fabric was found to be probably due to the plasma action effect on increasing in the fabric thickness and a change in fabric surface morphology. The change in the thermal properties of the LTP-treated wool fabric was in good agreement with the above findings and can be attributed to the amount of air trapped between the yarns and fibers. This study suggested that the properties changed by the LTP treatment can influence the final properties of the wool fabric. [ABSTRACT FROM AUTHOR]

Traditional fabrics utilize twisted yarns and the purpose of the twist is often misunderstood. The twist is introduced partly because of its effect on the fabric, but mostly its real function is to permit the manipulation of the yarns during processes leading to the final fabric. The current series of tests show that fabrics made of twistless yarns are remarkably strong and have many favorable characteristics. For example, both knitted and woven fabrics suffer much less shrinkage in the fabric forming process. Good cover can be obtained because the yarns flatten within the fabric structure. The changed disposition of the fibers tends to give a softer hand. The system is not without problems; for example, if the fibers are scoured before manufacture, it is difficult to remove the size. The frictional characteristics of the fibers are affected and this seems adversely to affect the tearing strength. Work is being carried out to eliminate the need to scour the fibers, and attempts are being made to draft the fibers when thoroughly wetted by a low-viscosity size recipe. The wetting, drafting, drying, and winding are carried out in a single continuous operation. Wet drafting is found to produce substantial advantages, particularly with cotton fibers. [ABSTRACT FROM PUBLISHER]

The moisture responses of plain jersey and 1 X 1 rib fabrics constructed from synthetic fiber-cotton blend yarns have been studied. The fabric responses include water vapor transmission, moisture imbibition, moisture regain, and air permeability. Measurements of the fabric strength and shrinkage are also reported.The fabrics were constructed from 24/1 yarn of cotton-nylon, cotton-polyester, and cotton-acrylic blends in 100/0, 80/20, 60/40, 50/50, 40/60, 20/80, and 0/100 percent.A simplified technique for measuring water vapor transmission through fabric was used to provide a means for com paring the blends. It was found that water vapor is transmitted through single thicknesses of plain jersey fabric faster than through equivalent rib fabrics, and significant increases in water vapor transmission occur as the synthetic com ponent of the cotton-synthetic blend is increased. Even greater relative increases in air permeability were observed with increasing synthetic-fiber content. It was, therefore, concluded that moisture vapor flow through knit fabric occurs almost entirely through the fabric interstices, and the hygroscopic nature of the fibers in the blend plays a minor roll in the moisture vapor transfer through fabric. Thus, it can be expected that garment comfort, at least as correlated with water and air permeability, should not be adversely affected by the addition of synthetic fibers to the blend. Moisture regain, moisture imbibition, and shrinkage decreased as the synthetic fiber content of the fabrics increased. [ABSTRACT FROM PUBLISHER]

Several commercially available proteins were grafted onto wool fabric using diepoxides as cross-linking agents and a 140-160°C cure. From 1.5 to 5.5% protein was grafted, onto the fabric to yield modified wools with moderate-to-good shrinkproofing properties, small losses in wrinkle recovery, and moderate-to-large increases in flexural rigidity. Collagen- extracted Colloid 5V grafted onto wool with glycerol diglycidyl ether (GDE) gave durable grafts with desirable properties, while other proteins (zein, casein, collagen-extracted Colloid I) with GDE gave protein-grafted fabrics with somewhat less desirable properties. Other commercial diepoxides gave unsatisfactory protein grafts to wool. [ABSTRACT FROM PUBLISHER]

The performance characteristics of nonwoven fabrics have been studied as a function of fiber properties, binder properties, and web construction. The particular type of nonwoven selected for study was a web of random-laid base fibers in which randomly placed thermoplastic fibers provide the bonds. The responses studied were those related to rupture, elastic, and handle (aesthetic) properties. Fourteen variables were investigated: Base fiber linear density, base fiber staple length, amount of crimp in base fiber, post-yield extension of base fiber, type of binder, linear density of binder, staple length of binder, binder concentration, mass per unit area of nonwoven, amount of needle looming, number of laminations per web weight, pressure of bonding, temperature of bonding, and time of bonding. The performance characteristics measured as a function of these variables were maximum tenacity at dry and wet conditions, elongation at dry and wet conditions, tear strength, abrasion resistance, elastic modulus at dry and wet conditions, proportional limit at dry and wet conditions, crease recovery, bending length, flexural rigidity, bending modulus, bulk density, and air permeability. Crimp, linear density, and staple length of the base fiber influence rupture, elastic, and handle prop erties, as expected. Binderproperties, other than type, have no effect due to the destruction of the fiber in the bonding process. Bonding conditions, particularly pressure and temperature, are extremely influential in all types of properties. These variables govern the effectiveness of the bonds. Concentration of binder is extremely important to all types of responses since it governs the number and distribution of bonds. Needle looming affects only rupture properties. [ABSTRACT FROM PUBLISHER]

The limiting oxygen index (LOI) technique provides a quantitative measure of reduced ftammability for fabrics over broad ranges of chemical treatment. Several conventional flame-retardant finishes for cellulosics gave linear LOI relationships with phosphorus content when compared at fixed nitrogen/phosphorus ratios. Tris(aziridinyl)phosphine oxide (APO) was an exception.Precise measurement of the role of N in enhancing the flame-retardant effectiveness can be made with this technique. The synergistic interaction of N and P can thus be described and measured. Two chemical systems were examined in depth, and it was possible to describe LOI as simple functions of N and P contents for each system. The synergistic effect did not predominate at a specific N/P ratio.LOI of about 0.26 is associated with a 5-in. char length in the vertical test for several fabrics, a sateen fabric being an exception. Fabric air permeability was found to be a primary factor governing chemical requirements and is probably more important than fabric weight.Other nitrogenous durable-press reactants are less effective than melamines. Complex relationships as functions of nitrogen content were noted at different phosphorus levels. [ABSTRACT FROM PUBLISHER]