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Sweating is thermo-regulatory behaviour that occurs when a person performs vigorous activity even in cold climatic condition. One of important component of sweat is the presence of lactate. Based on climatic condition, age, gender, maturity and nature of activity level, the change in lactate concentration is inevitable. Hence, the present study is focussed on the impact of change in the lactate concentration on the moisture transmission behaviour through the clothing. The purpose of this paper is to investigate the impact of changing lactate concentration on the moisture vapour transmission behaviour through multi-layered clothing ensembles.

For the investigation, sweat solution representing male and female sweat were taken for present study. Two different multi-layered ensembles consisting of either spacer or fleece as middle layer were considered. The water vapour permeability and drying rate test were done at standard atmospheric conditions. After testing, ANOVA analysis was done in order to determine the most significant parameters.

Fabric structure (constituent layers) behaved differently when tested individually and as the layered component with different sweat solutions. Water vapour permeability of sweat solution with higher lactate concentration was lower as compared to sweat solution with lower lactate concentration. Individual layers showed higher rate of vapour permeability with sweat solution containing lower lactate concentration as compared to multi-layered ensembles. Role of PU coated nylon fabric was predominant in case of multi-layered ensembles. Difference in transmission of sweat solution was found higher in case of uni-directional stitched multi-layer spacer ensembles whereas marginal difference was observed in case of bi-directional seamed multi-layer spacer ensemble. Drying rate of sweat containing lower concentration of lactate was higher as compared to the other sweat solution for all the selected fabrics. Density of liquid and amount of the water available for drying influenced the drying behaviour and thus accounted for difference in drying rate of sweat solution differing in the lactate concentration. The contribution percentage of layers, i.e. type of structure was higher (nearly 93–96%) compared to that of solution type (3.3–4.9%) in case of individual layers whereas in the case of the multi-layer ensembles; type of seam had maximum contribution percentage (71–77%) followed by solution type (10–15%). Type of layers had least contribution percentage (nearly 7–9%).

The findings from the study are expected to be realistic and important in designing and development of cold weather garment ensemble for different gender type depending on their activity level especially in case of military personnel and those performing combat activities.

This experimental work based will provide the insight about the behaviour of actual sweat transmission through the layered fabric ensembles and ways to prevent the accumulation of moisture near to human skin surface by manufacturing suitable design structures (in terms of layering composition and seam patterns) per the morphology and requirement of specific consumers.

The purpose of this paper is to describe a new transient approach for testing water vapor diffusivity of fabrics and fibrous assemblies.

An apparatus was designed and built in order to investigate the transient water vapor diffusivity of fabrics and fibrous assemblies, and the apparatus is validated by applying a theoretical model and comparing the result obtained by the desiccant cup method.

The transient water vapor diffusion test method permits rapid testing of small quantities of fabrics in a short amount of time. The method has an excellent correlation and agreement with the desiccant cup method. The variation of the new method is much smaller than the desiccant method. It also provided a way to study water vapor transfer through fibrous assemblies.

The paper introduces a new approach for testing water vapor diffusivity of fabrics and fibrous assemblies.

To clarify the principles and mechanisms of water vapour transfer by diffusion in waterproof breathable fabrics for clothing, experiments using a simple glass dish were carried out under steady state conditions with and without a temperature gradient in the climatic chamber. It was found that both vapour pressure and natural convection within the air gap affect water vapour transfer. The rates of water vapour transfer are ranked microfibre fabrics, cotton ventiles, PTFE‐laminated fabrics, poromeric polyurethane laminated fabrics, hydrophilic laminated fabrics, and polyurethane‐coated fabrics. In the presence of a temperature gradient, condensation was also found to be a major factor, especially at air temperatures below 0°C. Condensation occurred the least on the inner surface of PTFE‐laminated fabrics followed by cotton ventiles, microfibre fabrics, hydrophilic‐laminated fabrics, poromeric polyurethane‐laminated fabrics, and polyurethane coated fabrics.

The liquid water and water vapour transfer properties of fabrics play an important and decisive role in determining thermal comfort properties of clothing systems. The purpose of this paper is to analyse the effects of fabric composition (98 percent cotton–2 percent elastane and 100 percent cotton) and finishing treatments (rigid, resin, bleaching and softening) on the wicking, drying and water vapour permeability (WVP) properties of denim fabrics.

The research design for this study consists of experimental study. Two fabric compositions (98 percent cotton–2 percent elastane and 100 percent cotton) and four finishing treatments (rigid, resin, bleaching and softening) were evaluated to see the effects of elastane and finishing treatments on wicking, drying and WVP properties of woven denim fabrics. Results were analysed statistically.

Experimental results showed that the transfer wicking, drying and WVP values of denim fabrics were significantly influenced by fabric weight, fibre composition and finishing treatments.

The wicking ability of sweat from the skin to the outer environment of a skin contact fabric layer is the primary requirement.

As a result of the literature review, it was seen that there are some studies in the literature about comfort properties of denim fabrics, but there is no study concerning the water vapour transmission, wicking and drying properties of denim fabrics.

The paper aims to investigate thermal comfort properties, such as heat and moisture transmission through male business clothing systems, by using a sweating thermal manikin Coppelius that simulates heat and moisture production in a similar way to the human body and measures the influence of clothing on heat exchange in different environmental and sweating conditions.

Ten different combination of male business clothing systems were measured using the sweating manikin, under three environmental conditions (10°C/50 per cent RH, 25°C/50 per cent RH and −5°C), and at 0 and 50 gm⁻² h⁻¹ sweating levels, in order to evaluate the influence of environmental and sweating conditions on thermal comfort properties of clothing systems.

The results show how business clothing systems influence on the dry and evaporative heat loss between the manikin surface and environment in different environmental and sweating conditions.

When using sweating thermal manikin Coppelius, water vapour transmission (WVT) through and water condensation on the clothing can be determined simultaneously with the thermal insulation (I_t) of clothing system. Measured thermal comfort properties of clothing systems evaluated with a sweating thermal manikin can provide valuable information for the clothing industry by manufacturing/designing new clothing systems.

In this investigation, the heat and moisture transmission properties of male business clothing systems were measured in different environmental and sweating conditions. In the past few years, clothing materials containing microencapsulated phase‐change materials (PCMs) have appeared in outdoor garments, particularly sportswear; therefore, we decided to investigate the thermal comfort properties of different standard male business apparel, as well as male business clothing that contain PCMs used as liner and outerwear material.

The purpose of this study was to investigate the heat and moisture transmission through different types of textile materials or material combinations used for male business clothing.

In this study, eight different material combinations, which simulate four‐layer male business clothing system were tested using the sweating cylinder under two environmental conditions (10°C/65% RH and 25°C/65% RH), and at two sweating levels (100 and 200 gm⁻²h⁻¹), in order to evaluate the heat and moisture transmission properties of material combinations.

The results show how combinations of clothing materials that simulate male business clothing system influence on the dry and evaporative heat loss between the cylinder surface and two different environment conditions as well as to different sweating levels.

The sweating cylinder can be used for measuring the heat and moisture transmission through clothing materials or material combinations in order to find out the best combination of textile materials, which simulate clothing system. Measured thermal comfort properties of material combinations evaluated with a sweating cylinder can provide valuable information for the textile and clothing industry by manufacturing/designing new textiles and clothing systems.

The paper investigated the heat and moisture transmission through combinations of clothing materials that simulate male business clothing system. In the past few years, clothing materials containing microencapsulated phase‐change materials (PCMs) have appeared in outdoor garments, particularly sportswear; therefore, we decided to investigate the combinations of standard used textile materials as well as of materials, containing PCMs, which simulate male business clothing system.

Investigates whether water vapour transfer from the local environment of the human body at a relative humidity less than 100 per cent to a rainy or wind‐driven environment of relative humidity almost 100 per cent is possible. To identify whether prolonged rain has an effect on water vapour transfer in waterproof breathable fabrics, secondary experiments were carried out using a precipitator simulator covering a large area with severe rain. It was found that waterproof breathable fabrics breathe even under rainy conditions (with lower water vapour transfer rate), though encountering limitations under prolonged severe rain. The water vapour transfer rate was reduced under wind‐driven rainy conditions. More condensation was observed under rainy conditions on all fabrics except PTFE laminated fabrics.

Reports on an automated apparatus and test procedure to determine the convective and diffusive gas and vapor transport properties of small pieces of woven and nonwoven fabrics, membranes, and foams. The apparatus allows measurement of these properties in the very small quantities typical of material development programs, where the largest sample available may only be 1‐10cm² in area. The convection/diffusion test method is useful for determining the gas flow resistance property and water vapor diffusion properties from a single experimental run. This eliminates the need for two separate tests, which is the usual procedure. The apparatus may also be used to perform separate tests for the diffusion property or the air permeability property, which may have some advantages when materials exhibit strongly concentration‐dependent transport properties. The convection/diffusion test method is well‐suited for rapid screening and comparison of the properties of a large number of materials with widely‐varying transport properties.

To assess the effect of wind speed in practice, experiments were conducted under conditions of realistic wind velocities generated in the climatic chamber. The theoretical and experimental results were compared. In the theoretical model of forced convection between the human skin and the external environment the water vapour transfer rate was found to be proportional to V^0.81. The experimental results obtained when a layer of fabric was included showed that water vapour transfer is proportional to V^0.5. The rates of water vapour transfer for the fabrics ranked slightly differently from that seen under steady state conditions; microfibre fabrics, cotton ventiles, PTFE‐laminated fabrics, hydrophilic‐laminated fabrics, and poromeric polyurethane‐laminated fabrics. Condensation was reduced under windy conditions.

Water vapor trapped in the boundary layer between a person and the clothing creates discomfort and other unpleasant sensations. When that water vapor is prevented from leaving the clothing by external vapor barriers or impermeable layers, those psychophysical states are further exacerbated. One situation where that can be problematic is in office workplaces, and the seats that workers use for many hours every day. This study aims to evaluate the impact of different fabrics that are used for seat cover on water vapor retention.

The authors' method determines the behavior of contact surface humidity with a 50 kg sandbag on the seat to mimic the deformation of the seat materials due to the seated person's weight. Thus, the maximum increase in relative humidity (RH) after humidification of the seat surface (ΔRH-max), the time required to reach the maximum value of humidity (t-max) and the time constant (TC) after humidity starts to fall were derived.

Of the three different seat covers tested, the ΔRH-max of the wool were 7.3–8.8%, compared to 27.0–29.0% of the polyvinyl chloride (PVC), indicating more moisture absorption and transmission of the wool. The TC of the acrylic cover was 224–384 min compared to the 483–558 min of the PVC, which indicated a quick drying out feature of the acrylic.

The ΔRH-max, t-max and TC were all significantly correlated with the RH at the back thigh skin surface of the actual human participants.