The textile modification technique of calendering was used to change the cover factor of wearable textiles in order to improve the ultraviolet protection factor and decrease the amount of ultraviolet ...radiation transmitted through the fabric. Using optical microscopy and ultraviolet spectrophotometry, the quantifiable changes that occurred after repeated passes through the calender were measured. It was found that after one pass the uncovered area decreased by a factor of two and the ultraviolet protection factor increased by 200%. The thickness and air permeability of treated fabric decreased with repeated calendering. The bending stiffness remained nearly unchanged, and thus the mechanical properties were not altered substantially by the fabric compression.
We reported previously that treatment of polyamide 66 with a mixture of CaCl2/EtOH/water results in a significant increase of surface roughness. A higher surface roughness is correlated with greater ...light scattering propensity, and therefore we investigated if polyamide 66 fabrics treated with the mixture exhibit lower ultraviolet (UV) transmission. The work was performed on a commercially available plain-woven polyamide 66 fabric, and the UV protection factor (UPF) increased from a value of 25 (of the fabric as received) to >100 (after a 1-min treatment with the mixture). There was no significant change in cover factor of the fabric. As the solvent mixture is environmentally benign and the desired effects are obtained with short treatment times, we believe this process may be a more sustainable alternative to the use of UV absorbers that is the state-of-the-art technology at the present time. In this paper, we have described the treatment and its effects on substrate topography and mechanical properties.
Integration of sensors in textile garments requires the development of flexible conductive structures. In this work, cellulose-based woven lyocell fabrics were coated with copper during an ...electroless step, produced at 0.0284 M copper sulfate pentahydrate, 0.079 M potassium hydrogen L-tartrate, and 0.94 M formaldehyde concentrations. High concentrations led to high homogeneous copper reaction rates and the heterogeneous copper deposition process was diffusion controlled. Thus, the rate of copper deposition did not increase on the cellulose surface. Conductivity of copper coatings was investigated by the resistance with a four probe technique during fabric deformation. In cyclic tensile tests, the resistance of coated fabric (19 × 1.5 cm
) decreased from 13.2-3.7 Ω at 2.2 % elongation. In flex tests, the resistance increased from 5.2-6.6 Ω after 5000 bending cycles. After repeated wetting and drying cycles, the resistance increased by 2.6×10
. The resistance raised from 11-23 Ω/square with increasing relative humidity from 20%-80%, which is likely due to hygroscopic expansion of fibers. This work improves the understanding of conductive copper coating on textiles and shows their applicability in flexible strain sensors.
The goal of this study was to investigate the effect of differences in water vapor permeability (WVP) of outdoor jackets on moisture management, subjective perceptions and physiological parameters ...under conditions typically encountered in outdoor sports.
Four outdoor jackets differing only in their WVP were compared in a repeated measures study. A total of 19 subjects (nine females) were tested in a climatic chamber at 10℃ and 40% relative humidity. The protocol consisted of 15 min of rest, 50 min of treadmill running at 60% of the individual maximal running velocity, and 15 min of passive recovery.
We found that jackets featuring greater WVP helped to reduce relative humidity underneath the jacket, resulting in less sweat residue in the clothing system and drier skin during exercise and rest. Subjects were also able to perceive the differences in the microclimate and reported feeling more comfortable and drier in the more permeable jackets. However, WVP did not have a significant effect on oxygen consumption, heart rate, tympanic temperature, overall loss of subjects’ body mass or on perceived exertion.
It can be concluded that outdoor jackets with higher WVP benefit moisture management during submaximal exercise in cool temperatures by reducing relative humidity in the clothing system mostly during rest periods. This effect leads to a drier skin which favors perceived comfort and might reduce the after-chill effect. However, WVP of outdoor jackets neither significantly affects physiological responses nor perceived exertion during submaximal exercise in a cool environment.
The complex hierarchical structure of the wool fibre, both in terms of chemical and physical morphology, offer various components with differing, yet desirable properties. This study showed how the ...wool fibre can be systematically reverse engineered into its constituent components, with minimal to no chemical or physical change to the desired component. Through a combination of targeted chemical and mechanical attack, the cuticle scales where separated from the cortex. The cortex was then broken down into the cortical cells, through mechanical agitation. Moreover, the breakdown of the cortical cells can be achieved through an enzymatic action, producing macrofibrils. The subcomponents were then utilised to form wool-keratin structures, using a keratin extract as the matrix. Control of the placement of the components can alter the properties of the final product.
An ideal absorbent dressing requires high absorbency, moisture retention and antimicrobial properties. In this study, the application of silver-containing spacer fabric as an antimicrobial wound ...dressing was investigated. The silver distribution on the spacer fabric was different from that of layer-by-layered fabric. The middle layer of the spacer fabric contained much higher amounts of silver, while the layer-by-layered fabric had lower silver contents in its middle layers than its surface layers. The silver-containing spacer fabric could keep a better moist environment for the wound than commercial foam dressing. For the silver-containing spacer fabric, 100% reductions in viability were observed for both the Gram-positive Staphylococcus aureus and the Gram-negative Klebsiella pneumoniae after only 1 h. The spacer fabric could keep most of the silver in its middle layer and kill bacteria in the middle layer rather than at the wound contact surface. This way to absorb wound exudates and kill bacteria within the dressing reduces the silver concentration on the wound bed, and therefore this could be an efficient way to lower the potential of silver entering the human body, and prevent silver toxicity and accelerate wound healing.
An ideal absorbent dressing requires high absorbency, moisture retention and antimicrobial properties. In this study, the application of silver-containing spacer fabric as an antimicrobial wound ...dressing was investigated. The silver distribution on the spacer fabric was different from that of layer-by-layered fabric. The middle layer of the spacer fabric contained much higher amounts of silver, while the layer-by-layered fabric had lower silver contents in its middle layers than its surface layers. The silver-containing spacer fabric could keep a better moist environment for the wound than commercial foam dressing. For the silver-containing spacer fabric, 100% reductions in viability were observed for both the Gram-positive
Staphylococcus aureus
and the Gram-negative
Klebsiella pneumoniae
after only 1 h. The spacer fabric could keep most of the silver in its middle layer and kill bacteria in the middle layer rather than at the wound contact surface. This way to absorb wound exudates and kill bacteria within the dressing reduces the silver concentration on the wound bed, and therefore this could be an efficient way to lower the potential of silver entering the human body, and prevent silver toxicity and accelerate wound healing.
Silver-containing wound dressing based on spacer fabric promotes exuding wound healing through absorbing exudates, keeping moisture, killing bacteria and reducing silver contacting with wound.
Wool in outdoor clothing systems is stated to be a good temperature and humidity regulator giving the wearer a warm and dry feeling during physical activities in the cold. The objective was to ...compare two different battings (sheep wool “tirolwool” (TW) versus polyester microfiber (PMF)) in an outdoor jacket of a two-layer outdoor clothing system consisting of a shirt and jacket on the heat and moisture management and comfort sensation during a moderate mountain walking protocol which was followed by a cool-down phase in the cold (−5℃, 43% relative humidity). Due to its beneficial moisture management properties it was hypothesized that TW in the outermost layer would cause a higher skin and core temperature, reduce the after chill effect, increase moisture transfer, decrease moisture accumulation within the clothing system, and lead to more pleasant comfort sensations. Twelve sport students performed the simulated walking protocol (60 min, 7.7% inclination, 5 km/h) and cool-down phase (20 min) with TW and PMF in a climatic chamber. The use of TW compared to PMF was stronger moisture absorbent led to a dryer shirt (p = 0.043) and lower humidity underneath the shirt and jacket (chest: p ≤ 0.05). Core temperature (p = 0.017) and skin temperature drop (chest: p = 0.003) were attenuated with TW after the physical activity. Therefore, the after chill effect was reduced with TW but moisture accumulated to a higher extent in the jacket (p = 0.001), which might lead to a longer drying rate. Correlation analysis revealed that tested underwear blended with merino wool, elastane, and polyamide might feel less scratchy in the slightly damp state than in the dry state.
The objective of this investigation was to achieve an understanding about the relationship between heat stress and performance limitation when wearing a two-layerfire-resistant light-weight workwear ...(full-clothed ensemble) compared to an one-layer short sports gear (semi-clothed ensemble) in an exhaustive, stressful situation under moderate thermal condition (25°C). Ten well trained male subjects performed a strenuous walking protocol with both clothing ensembles until exhaustion occurred in a climatic chamber. Wearing workwear reduced the endurance performance by 10% (p=0.007) and the evaporation by 21% (p=0.003), caused a more pronounced rise in core temperature during submaximal walking (0.7±0.3 vs. 1.2±0.4°C; p≤0.001) and from start till exhaustion (1.4±0.3 vs. 1.8±0.5°C; p=0.008), accelerated sweat loss (13±2 vs. 15±3gmin−1; p=0.007), and led to a significant higher heart rate at the end of cool down (103±6 vs. 111±7bpm; p=0.004). Correlation analysis revealed that core temperature development during submaximal walking and evaporation may play important roles for endurance performance. However, a critical core temperature of 40°C, which is stated to be a crucial factor for central fatigue and performance limitation, was not reached either with the semi-clothed or the full-clothed ensemble (38.3±0.4 vs. 38.4±0.5°C). Additionally, perceived exertion did not increase to a higher extent parallel with the rising core temperature with workwear which would substantiate the critical core temperature theory. In conclusion, increased heat stress led to cardiovascular exercise limitation rather than central fatigue.
•Light-weight workwear limited performance by 10% under moderate thermal condition.•Evaporation and core temperature played important roles for endurance performance.•Evaporation was reduced by 21% but critical core temperature (40°C) was not reached.•Sweat loss was accelerated and cardiovascular stress was higher during recovery.•Increased heat stress rather led to cardiovascular limitation than central fatigue.
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