Sweat Absorption Research Articles

Digital Sublimation Printing on Knitted Polyamide 6.6 Fabric Treated with Non-Thermal Plasma.

The garment industry demands stamping processes that are increasingly more agile and less damaging to the environment. In this scenario, digital printing, with the sublimation transfer printing technique, presents itself as a viable option for synthetic textile substrates. Among the synthetic fibres, polyamide (P.A.) fibres stand out, as they are light, soft, durable, and boast moderate sweat absorption; however, before sublimation, superficial treatment is necessary in order to present good results such as withstanding washing and maintaining colour intensity. This study addresses the surface modification of the PA6.6 textile substrate by activating non-thermal plasma at atmospheric pressure to receive dye through the sublimation method with dispersed dye. The knitted PA6.6 fabric surface treatment was performed with plasma application at atmospheric pressure using air in the Plasmatreater AS400 equipment. The sublimation transfer effects were evaluated by wash fastness and colourimetric tests. To assess the wettability effect of the control and treated samples, a contact angle test was carried out on PA6.6 samples. Fourier transform infrared spectroscopy (FTIR) proved the changes in chemical functional groups in the fibres. The results showed a decrease in the contact angle of the textile surface, 4–5 grayscale results for colour change and transfer for washing, and an increase in colour strength. In the FTIR tests, there is an increase in the transmittance value of aromatic, carboxylic groups (C=O, 580 cm−1), amides (N=H, 1630 cm−1), and methyl groups (CH 1369 to 1463 cm−1) as well as the presence of new functional groups in the 3064 cm−1 and 2860 cm−1 bands. These conditions allowed sublimation in the knitted PA6.6 fabric and showed increased colour strength and good wash fastness.

Impact of Sweat Absorption on the Electrostatic Potential Build-Up in Cotton and Nylon Fabric Samples

Impact of Sweat Absorption on the Electrostatic Potential Build-Up in Cotton and Nylon Fabric Samples

TINJAUAN POLYESTER PADA JERSEY SEPEDA

This research contains the “overview of polyester on bicycle jersey”. Polyester fabric is a fabric that is often used for bicycle jerseys because it has a high coefficient of elasticity and sweat absorption which is directly channeled to the outer layer of the jersey, thus keeping the body dry and comfortable during cycling. Bike jersey is designed in such a way as to support cyclists or racers in carrying out their activities. The choice of polyester type and the difference between the Mountbike jersey and the Roadbike jersey have a role to affect the comfort while cycling because cycling with the right clothes will further increase the benefits of cycling. To study the polyester review on the bicycle jersey, the author uses qualitative methods and analysis techniques using ergonomic theory. From the results of the discussion, it can be concluded that almost all types of polyester meet the material comfort standards, but there are differences in treatment in fulfilling safety aspects.

Fiber-crafted biofuel cell bracelet for wearable electronics

Wearable devices that generate power using sweat have garnered much attention in the field of skin electronics. These devices require high performance with a small volume and low production rate of sweat by living organisms. Here we demonstrate a high-power biofuel cell bracelet based on the lactate in human sweat. The biofuel cell was developed by using a lactate oxidase/osmium-based mediator/carbon nanotube fiber for lactate oxidation and a bilirubin oxidase/carbon nanotube fiber for oxygen reduction; the fibers were woven into a hydrophilic supportive textile for sweat storage. The storage textile was sandwiched between a hydrophobic textile for sweat absorption from the skin and a hydrophilic textile for water evaporation to improve sweat collection. The performance of the layered cell was 74 μW at 0.39 V in 20 mM artificial sweat lactate, and its performance was maintained at over 80% for 12 h. Furthermore, we demonstrated a series-connection between anode/cathode fibers by tying them up to wrap the bracelet-type biofuel cell on the wrist. The booster six-cell bracelet generated power at 2.0 V that is sufficient for operating digital wrist watches.

Smart polyester fabric with comfort regulation by temperature and moisture responsive shape memory nanocomposite treatment

Recently, clothing comfort and ease of use have become an indispensable expectation especially in sports and functional clothing which have led researchers to focus on development of smart textiles including new functionalities such as active thermoregulation. Therefore, a novel nanocomposite finishing treatment consisting of temperature responsive shape memory polyurethane (SMPU) and cellulose nanowhiskers (CNWs) was developed and applied to polyester fabric to produce smart fabric having dual responsive performance to moisture besides temperature. Water vapour, air permeability and sweat absorption properties were investigated under different temperature and relative humidity conditions to test thermoregulation performance of the treated fabrics. Physical, mechanical properties (weight, thickness and bursting strength) and durability of treated fabrics were also tested. Morphology, chemical compositions and thermal characterization of treated fabrics were investigated by Scanning Electron Microscope (SEM), Fourier Transform Infrared Spectroscopy (FT-IR), Differential Scanning Calorimeter (DSC) and Thermogravimetric (TG) analyses, respectively. It was found out that polyester fabric exhibited dynamic breathability and sweat absorption with temperature and relative humidity of body or environmental conditions thanks to the obtained dual responsive shape memory function. Also, mechanical and end use performances such as bursting strength and washing fastness of polyester were enhanced with this treatment. Summing up, SMPU-CNW nanocomposite treatment can be a good alternative for smart sports clothing having thermoregulation function for enhanced comfort besides desired mechanical and end use performances.

Heat and sweat management by a cycling garment impact thermal sensations during exercise in hot and moist conditions

The aim of this study was to investigate the impact of six cycling garments constituted of different materials, during a constant moderate cycling exercise in a hot and moist environment on (a) thermal sensation, (b) change of thermoregulatory parameters, and (c) sweat absorption. Ten cyclists from an amateur to a professional level (age: 21 ± 4.6 years, height: 180.1 ± 6.7 cm; body mass: 70.9 ± 7.8 kg, body mass index: 21.8 ± 1.6) performed six-twenty min pedaling sessions at 4 on CR 10 Borg scale in a hot and moist environment (environmental temperature = 32.8 ± 0.9 °C and relative humidity = 63.4 ± 8.5%), wearing six garments composed of different materials. Heart rate, power output, and core temperature were measured continuously. Skin temperature in 16 regions of interest was measured with an infrared camera every 5 min. The rating of perceived exertion and the thermal sensations was measured every two min. The sweat absorbed by the garment during the exercise was also quantified. The absence of differences concerning power output, heart rate, core temperature, and the mean skin temperature between garments suggested that non-physiological parameters could also explain the significant differences of mean thermal sensations observed between garments (p < 0.05). Indeed, the quantity of sweat absorbed by garment was significantly positively correlated to mean thermal sensations during the exercise (p < 0.05), suggesting that a bad sweat evacuation by the garment involves an increase of thermal sensations. Moreover, the significant relation predicting mean thermal sensations with the quantity of sweat absorbed, the evolution of the skin temperature in the low back, and in the abdomen regions between 0 and 20 min indicated that local heat exchanges by garment would impact thermal sensation.

Reusable face mask for the knitted fabric with finishes treatment

This will surgical mask beneficially for the user of village people and communities, at home and at health care facilities in areas. Experimental work was done to study the reusable face masks knitted fabric of the thickness, Pore size analysis, finishing characteristics performance and comfort &amp; moisture management properties. According to the analysis, it has observed that all the parameters are significantly affected. I have some tested above the surface and I found that the results are good face masks. It will help to prevent covid 2019 virus infection. It is able to anti-dust pollution, washable &amp; reusable product. It is faster sweat absorption and provides disease protection, relief from bad odours and more for ultimate best performance by face masks. It will help to catch the bacteria shed in liquid droplets and aerosols from the wearer's mouth and nose. This is a reusable surgical mask. This will use mask reusable fifteen times and very low cost this product. Now present-day surgical mask available in the market only one time used. Now present situation, it has not easily available surgical mask in the small town or village area. Now present-day available some mask inside market did not follow any technical specification standard. Now the present day has we main motif for the easily available good quality mask for the village &amp; small town. It will be easily available for the low cost &amp; reusable surgical mask.

Dual responsive wool fabric by cellulose nanowhisker reinforced shape memory polyurethane

ABSTRACTShape memory wool fabrics having both temperature and moisture responsiveness were fabricated by a functional nanocomposite treatment comprising of shape memory polyurethane (SMPU) and cellulose nanowhisker (CNW). Water vapor permeability and sweat absorption properties were investigated under different temperature or relative humidity values to test smart comfort capabilities of the treated fabrics. Besides, felting shrinkage and weight loss of the fabrics after repeated washing cycles were investigated for end use performance. It was found out that the wool fabrics functionalized by nanocomposite treatments exhibited dynamic breathability and sweat absorption changing with temperature and relative humidity of body or environment. Moreover, nanocomposite application enhanced rigidity, tear strength, anti‐felting and weight loss performances of the wool fabric. 20 wt% CNW concentration can be suggested for thermal comfort, mechanical and end use performance enhancements to obtain smart garments having dynamic responsiveness to both body physiological and environmental changes. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 137, 48674.

Multilayer Sweat-Absorbable Textile Electrode for EEG Measurement in Forehead Site

A multilayer sweat-absorbable flexible textile dry electrode for EEG measurement in forehead site was presented in this paper. With the development of BCI and wearable healthcare devices, the demand for long-term EEG monitoring, especially in the forehead site, has been increasing. However, current EEG electrodes cannot fulfill this demand, as wet electrodes need complex operations and conductive gels, and majorities of dry electrodes exhibit unacceptable high impedances. On the other hand, in motion or hot and moisture environment, the human body inevitably produces sweat that leads to short circuits or crosstalk interferences between neighboring electrodes, while current electrodes cannot deal with this situation effectively. To address the above-mentioned issues, a novel flexible dry electrode is designed using multilayer textile materials, including conductive fabrics and sweat absorption acceleration layer, which is able to absorb sweat effectively and further take the sweat as an electrolyte to enhance the conductivity. It also exhibits excellent conductivity with an electrode-scalp impedance superior to the wet electrode and other major electrodes in the literature. A good long-term stability in impedance was observed among current electrodes. A series of tests proved that the electrode was suitable for forehead EEG monitoring in daily life activities with a convenient and quick setup procedure as well as advantages of lightweight, adequate flexibility, and wearing comfort.

The use of infrared thermal imaging to measure spatial and temporal sweat retention in clothing

In our previous laboratory study a ‘destructive’ gravimetric method was developed to quantify local garment sweat absorption. While this currently is the only methodology that permits direct and analytical measurements of garment regional sweat absorption, the latter approach is time-consuming and expensive, therefore, of limited applicability. As such, in this study, we wanted to assess whether infrared thermography could be used as an indirect method to estimate garment regional sweat absorption, right after exercise, in a ‘non-destructive’ fashion. Spatial and temporal sweat absorption data, obtained in our previous study, were correlated with spatial and temporal temperature data obtained in the same experiment with an infrared thermal camera. The data suggest that infrared thermography is a good tool to qualitatively predict regional sweat absorption in garments at separate individual time points; however, temporal changes are not predicted well, due to a moisture content threshold above which variations in sweat content cannot be discriminated by further temperature changes.

Spatial and temporal migration of sweat: from skin to clothing

PurposeMoisture accumulation in clothing affects human performance and productivity through its impact on thermal balance and various aspects of discomfort. Building on our laboratory’s work on mapping sweat production across the body, this study aimed to obtain detailed spatial and temporal maps showing how this sweat migrates into a single clothing layer (T-shirt) during physical exercise.MethodEight male participants performed running exercise in a warm environment. Garment sweat absorption was mapped over a total running time of 50 min, in 10 separated running trials of different durations (5 min increments). After running, the garment was dissected into 22 different parts and local sweat absorption (ABSlocal) was quantified by weighing each garment part before and after drying. From ABSlocal, garment total sweat absorption (ABStotal) was estimated.ResultsAfter 50 min, Tcore rose from 37 ± 0.2 to 38.6 ± 0.3 °C, HR increased from 69 ± 15 to 163 ± 12 bpm (p < 0.001), GSL was 586 ± 86 g m−2. Clear patterns of sweat absorption reduction from superior-to-inferior and from medial-to-lateral T-shirt zones were observed, with the mid back medial and the low front hem showing the highest, respectively.ConclusionsQuantitative data on garment total and regional sweat absorption were obtained and considerable variation between different garment zones was identified. These data can support the development of sport and personal protective clothing with the end goal to prevent workers’ heat-related injuries as well as maximise human performance and productivity.

Spirality in Knitted Fabric

Knit wear industry is growing at a faster rate across the globe and technological innovations contribute a lot in the success of industry. Knitted cotton fabric is considered ideal for next-toskin wear. Knit wear fabrics are popular because of their excellent properties of comfort, softness, sweat absorption, durability and softness. The dimensional stability is a serious problem with reference to quality. Quality of the fabric is of prime concern in placement of new ties between buyers and manufacturers. Consumers, now days, are becoming increasingly concerned and aware of fabric quality and accept higher quality standards than ever before. Pakistan’s knit wear industry is lagging behind the world knitting industry due to its less command and control over quality awareness and implementation of quality standards. Various defects in knitted fabrics affect the quality but spirality is the most common fault that affects the single jersey knit wear fabric. Single jersey fabric is mostly used for T-Shirts, sports wears and under garments, so position of seam is very important in the exact shape of the product, more is spirality, more de shaped is the end product.

Evaluation of thermal, moisture management and sensorial comfort properties of superabsorbent polyacrylate fabrics for the next-to-skin layer in firefighters’ protective clothing

This research investigated the transport properties (such as thermal resistance, water vapor resistance and air permeability), moisture management capacity and sensorial properties of some knitted structures of superabsorbent polyacrylate in order to explore their potential as next-to-skin layers in firefighters’ protective clothing in Australia. Test results using these fabrics were compared with the currently used next-to-skin woven fabric. Three different knitted structures (i.e. jersey, rib and interlock) were selected for the study in addition to the current woven fabric in use by Australian firefighters. It was observed that the knitted fabric samples of superabsorbent polyacrylate retained higher amounts of water compared to the fabric sample currently used in the firefighters’ clothing. However, the woven fabric sample dried at a faster rate. Hence, a blended fabric of polyacrylate with the current Nomex® fabric can help in higher sweat absorption and faster drying. The thermal and water vapor resistance of jersey fabric was the lowest, which may better facilitate the transfer of metabolic heat and vapor to the environment, resulting in better thermal comfort. Furthermore, all the fabric samples showed a low coefficient of friction (∼0.2), which indicated less tactile discomfort if the fabrics are worn as the next-to-skin layer in the firefighters’ clothing. The overall moisture management properties of the fabric samples were rated as fair to good. The findings of this research suggest that the superabsorbent material has the potential to be used in place of the existing next-to-skin layer of firefighters’ protective clothing, with better sweat absorption capacity and thermal comfort.

Paper] Sweat Absorption Reduces the Frictional Force Between a Finger Pad and the Surface of a Flat Plate

Paper] Sweat Absorption Reduces the Frictional Force Between a Finger Pad and the Surface of a Flat Plate

The effect of moisture and air gap on the thermal protective performance of fabric assemblies used by wildland firefighters

The thermal protection performance (TPP) provided by fabric assemblies used by wildland firefighters is greatly affected by both the moisture and the air gap trapped in multilayer fabrics. In this paper, the effect of moisture, coupled with air gap on TPP was analyzed under radiant heat exposures of 21 kW/m2. The air gap sizes from 0 to 5.2 mm were analyzed using an air gap height regulation device; the moisture content of the multilayer fabric combinations around 0–70% were obtained by spraying distilled water to simulate varying amounts of sweat absorption. The results obtained indicate that certain air gaps entrapped in multilayer fabric system have a positive effect on TPP for both dry and wet multilayer fabric combinations. However, obvious trend changes in thermal protection were observed among dry and wet configurations when the air gap was moved to different positions. For the wet configurations, the second-degree burn time increased as the air gap moved further from the heat source, which was contrary to burn time response under dry conditions. These findings suggest that the complicated reciprocal effect of air gap and moisture on thermal protection should be both considered in analyzing the TPP of fabric assemblies.

Difference in hydrophobic and hydrophilic multilayered systems

Functional clothing, sportswear and military uniforms, are mainly made of polyester or cotton fabrics for dealing with sweat absorption and heat transfer produced by the human body. The human body typically wears two or three garments, such as innerwear, T-shirt, and jacket, thus comprising a multilayered system. Garments’ responses to heat transfer and vapor flow differ depending on whether their physical structures are hydrophobic or hydrophilic. Hence, this study analyzes differences in heat transfer and vapor flow, induced by the human body covered with multilayered garment systems, consisting of three polyester or cotton layers. In particular, it verifies three differences in the heat transfer and relative humidity, amount of relative humidity, and response time of thermal equilibrium in multilayered systems by using a new measurement system, “H&M evaluation device”. Resultant data provide precise information regarding several differences in hydrophilic and hydrophobic multilayered fabric systems.

Design of a novel comfort liner for a motorcycle helmet

Natural fibres are nowadays increasingly being employed for producing protective clothing and sportswear. Due to economic and/or environmental considerations they are replacing synthetic materials. The present work provides an insight into the design and development of a novel comfort liner for a motorcycle helmet. The liner is produced from wool and Tunisian alfa fibre. The plant of the alfa fibre is abundantly available in Tunisia. Furthermore, we describe a design concept for a liner that uses these natural fibres and phase change material to improve sweat absorption and perception of thermal comfort. The raw material, the processes involved and the solution to use the phase change material are analysed. The novel comfort liner can facilitate breathability and evaporative transfer of heat in the safety helmet. In addition, it increases comfort, well-being, and provides an indirect message to use natural fibres for textile support to preserve our environment.

Evaluation of surface characteristics of inner layer fabrics suitable for structural firefighters’ clothing

Effective firefighters’ clothing design requires great consideration of physiological comfort factors including sensorial or tactile comfort. The friction between the fabric surface and the skin, and the fabric surface roughness are the two important components in the evaluation of the sensorial comfort of fabrics and materials. The objective of this study is to investigate and compare the material surface characteristics of fabrics suitable for the inner layer of structural clothing for firefighters. We quantitatively examine and evaluate the effects of the fabrics’ composition, construction and their physical parameters on the surface characteristics, as relevant to the practical wear and maintenance of the garments. In addition, the influence of the presence of moisture in the fabrics due to the sweat absorption during strenuous physical activity on the fabrics surface characteristics is addressed.

Tribological evaluation of sportswear with negative fit worn next to skin

Compression garments are constructed to have a negative fit where the size of the garment is smaller than that of the body over which they are fitted. Due to this negative fit, these types of garments generate pressure on the underlying tissue of the human body where the inner surface of these garments is in full contact with the wearer’s skin. Sensorial or tactile comfort is an important part of an overall physiological comfort of sport apparel. The friction between fabric and skin and the fabric surface roughness are two important components in evaluation of the sensorial comfort of fabrics and materials. The objective of this study is to investigate and compare the material surface characteristics of fabrics suitable for the sport compression garments under conditions similar to those when such garments are worn. The study quantitatively examines and evaluates the effects of fabric construction, physical structural parameters and especially fabric elastic deformation on the fabric surface topography as relevant to the practical wear of sport garments with negative fit made from it. In addition, the influence of the presence of moisture in the fabrics due to the sweat absorption during strenuous physical activity on the textile surface characteristics is addressed.

Identification of anabolic steroids in serum, urine, sweat and hair: Comparison of metabolic patterns

Anabolic steroids usually undergo a complex metabolism which is mainly dependent on structural variation and application pathway. In contrast to doping analysis, where the presence of a prohibited substance constitutes a doping offence without regarding the origin or application, in forensic cases any information related to anabolic steroids may be required to evaluate the cause of death, liability of defendants, or self-consumption. 19-Norsteroids proved to be appropriate model compounds for the investigation, because of their prevalence in recent doping cases, analytical and biochemical similarity to endogenous steroids, well explored biochemistry, and the availability of numerous reference standards. Typical urinary metabolites are conjugates of terminal biotransformation products like norandrosterone–glucuronide, which are relatively unspecific and do not reveal details about administration time, pathway, dosages or structural details. Therefore, metabolic patterns in blood, hair and sweat were examined to study metabolism, distribution and incorporation behaviour of the steroids and hence the traceability in the respective matrices. Concentration profiles of the steroids in blood and the resulting bioavailability show distinct particularities after oral or transdermal application of steroids. Oral application of steroid precursors is followed by extensive first pass biotransformation of the steroid to inactive metabolites, while transdermal administration appears to be an efficient pathway, leading to effective and durable concentrations of active steroids in blood. Due to the mutual similarity of metabolic patterns in hair and sweat corresponding to the regional presence of sweat and sebum glands, steroid incorporation appears to proceed mainly via sweat absorption.