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The purpose of this paper is to investigate the effect of air and vapor permeability of jacket materials on ventilation, heat and moisture transfer.

Clothing ventilation (V), thermal insulation (I) and vapor resistance (R _e ) of three jackets made of different materials (normal textile, PVC and “breathable” membrane coated textile), worn on an articulated thermal manikin in a controlled climate chamber, were measured under various conditions, respectively. The various conditions of microenvironment ventilation were created by making the manikin stand and walk, combined with three wind speeds of <0.2, 0.4 and 2.0 m/s, respectively.

In the condition without any forced convection, the air permeability makes no big difference to dry and evaporative heat transfer among the jackets, while the vapor permeability plays a big role in the evaporative heat loss. In the condition with forced convection, the dry heat diffusion is strongly coupled to the evaporative heat transfer in air and vapor permeable textile material.

The effects of ventilation on heat and moisture transfer varies because of different ways of ventilation arising: penetration through the fabric is proven to be the most effective way in vapor transfer although it does not seem as helpful for dry heat diffusion.

The achievements in this paper deepens the understanding of the process of the dry and evaporative heat transfer through clothing, provides clothing designer guidance to choose proper materials for a garment, especially work clothing.

Sleep is a vital and a basic activity of human life and it is a physiological need for human body. Sleep quality is directly influenced by the comfort conditions of sleep environment. The purpose of this paper is to define the role of textile materials utilized as bed fabrics on air and mass transfer from the human body.

Thermal conductivity, thermal resistance, thickness, water vapour permeability and air permeability properties of fabrics were analyzed and statistically evaluated. Thermal conductivity and resistance measurements were performed in Alambeta test instrument. Water vapour permeability tests were done according to the Rotating Platform method, and air permeability was measured in FX 3300 Textest air permeability tester. Relationships between comfort parameters were statistically evaluated with correlation analysis.

Comfort is a major concept in the determination of overall life quality as well as sleep quality of a resting person. Therefore academic studies about thermal comfort prediction of sleep environment and bed surface fabrics are of great importance. This study investigates conventional mattress ticking fabrics in terms of comfort parameters and defines the important fabric properties on comfort parameters.

Sleep comfort is a promising area in textile comfort studies with its dynamics different from body thermal comfort during daily life. However, in general comfort studies are about garment materials which are in direct contact with the skin. This study tries to define the comfort status of textile materials which have indirect contact with the human body surface during sleep duration.

The purpose of this paper is to evaluate the water vapour permeability and mechanical properties of a solventless epoxy – nano‐platelet nano‐composite system compatibilised with an amino‐silane.

The performance of a nano‐platelet reinforced coating composite was studied with reference to the water vapour permeability and mechanical properties. The effect of addition of coupling agent on these properties was also studied.

The addition of nano‐platelets to the solventless epoxy system resulted in an increased water vapour permeability which was reduced on the addition of coupling agent. The talc‐based films showed a better performance as compared to the montmorillonite based coatings. The mechanical properties of the films increased though the addition of coupling agent showed a larger increase. The gloss of the coatings was compromised on addition of nano‐particles. Comparing coupling agents, the primary amine based silane showed better performance and lower tactoid formation as compared to the secondary amino silane based coupling agent.

The addition of nano‐particles to solventless and other eco‐friendly coatings needs to be studied further. Various other coupling agents could be studied to further improve the performance of these coatings.

The formulation developed could be used to reduce the water vapour permeability and performance of solventless epoxy coatings, which could be used as anti‐corrosive coatings.

The study of performance of nano‐particles in solventless epoxy coatings and their effect on water vapour permeability could increase performance of these reduced VOC coatings.

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.

Unlike other materials, textiles associate with aesthetic and mechanical properties such as flexibility and removability that allow them to be deployed or folded as required and which make them good candidates for clothing and furnishing but also, eventually, for other applications such as building. Actually, the clothing should ensure appropriate heat and mass transfers between the human body and its environment in order to maintain the thermo-physiological comfort. For that, it is important to determine water vapor permeability (WVP) of textile. Several normalized procedures with variants depending on the nature of the tested material exist to measure the WVP. One of the methods used is the “dish method” described by the British Standard (BS 7209). The purpose of this paper is to determine the influence of the test parameters on the WVP measurements.

Consequently, WVP of different textiles was measured while varying several parameters like: nature of fabrics, air layer thickness, vapor pressure gradient and air velocity.

A decrease in the WVP values was observed with an increase in the air layer thickness and the number of textile layers. On the other side, an increase in the water pressure gradient induces an increase in the WVP value. Finally, it was also observed that air velocity has an impact on the WVP measurements.

In addition to intrinsic properties of fabrics, i.e., nature of fiber, woven structure, the influence of the several extrinsic properties, i.e., the influence of the air layer thickness, the number of textile layers, the vapor pressure gradient and the air velocity, on the WVP were investigated. Some researchers have already investigated the impact of these parameters on the WVP measurement separately. However, this study presents a difference from other studies that it takes into account the influence of the both intrinsic and extrinsic properties on WVP. In addition to these, this work combine several extrinsic properties which are presented separately during other studies. The first time, in this study the influence of the air velocity on WVP was investigated. Results on both hydrophilic and hydrophobic fabrics showed a great variation in the results when varying the location of the cups inside the climatic chamber. This is the reason why future studies look at studying more deeply the effect of air velocity on the WVP properties on different types of fabrics by connecting WVP values with air velocity values. It is also planned to make tests with the rotation device and by fixing the value of the temperature and RH. The objective will be to obtain reliable values that do not take into account the effect of air velocity.

The purpose of this paper is to investigate effect of material properties in 3D knitted fabrics on thermo-physiological comfort.

In the present study six different spacer fabrics were developed. Among these six fabrics, it was classified into two groups for convenient analysis of results, the first group has been developed using polyester/polypropylene blend with three different proportion and second group with polyester/polypropylene/lycra blend having another three different composition. As a spacer yarn, three different types of 88 dtex polyester monofilament yarn and polyester multifilament yarns (167 dtex and 14.5 tex) were used and 14.5 tex polypropylene and 44 dtex lycra multifilament yarns were also used for the face and back side of the spacer fabrics (Table I). These fabrics were developed in Syntax Pvt Ltd Czech Republic.

The main influence on the water vapour permeability of warp knitted spacer fabrics is the kind of raw material, i.e. fibre wetting and wicking. Also there is no correlation between air permeability and water vapour permeability. It is found that both air permeability and thermal conductivity are closely related to the fabric density. It is also found that the fabric characteristics of spacer fabric show a very significant effect on the air permeability, thermal conductivity and mechanical properties of spacer fabric. Therefore, selection of spacer fabric for winter clothing according to its fabric characteristics.

The main objective of the present study is to produce spacer knitted 3D fabrics suitable for defined climatic conditions to be used as clothing or in sports goods.

New 3D knitted spacer fabrics can be produced with improved comfort properties.

This paper investigates the thermal comfort properties of quilted (jersey cord) fabrics produced with different width of diamond pattern, different filling yarn linear density and different types of material.

A total of 12 fabrics were knitted by varying the width of diamond pattern (1 and 3 cm), the filling yarn linear density (300 and 900 denier) and the type of materials (cotton, polyester and their combination). In this regard, air permeability, thermal conductivity, thermal resistance, thermal absorptivity and relative water vapor permeability of these fabrics were measured and evaluated statistically.

The results showed that fabrics knitted using cotton yarn in both front and back surfaces exhibit higher thermal conductivity, thermal absorptivity and relative water vapor permeability characteristics; whereas samples knitted using polyester yarn in both surfaces have higher air permeability and thermal resistance. As the linear density of filling yarn increases, thickness and thermal resistance of the samples increase and air permeability, thermal conductivity, water vapor permeability characteristics decrease. When the effect of the width of diamond pattern compared, it is seen that an increase in the width of pattern lead to an increase in thickness and thermal resistance and a decrease in thermal conductivity, thermal absorptivity and water vapor permeability values.

Many researches were carried out on the thermal comfort properties of knitted fabrics, however there is a lack of research efforts regarding thermal comfort properties of quilted fabrics.

The purpose of this paper is to present the thermal comfort properties of single jersey knitted fabric structures made from bamboo, tencel and bamboo-tencel blended yarns.

Bamboo, tencel fibre and blends of the two fibres were spun into yarns of identical linear density (30s Ne). Each of the blended yarns so produced was converted to single jersey knitted fabrics with loose, medium and tight structures.

An increase in tencel fibre in the fabric had led to a reduction in fabric thickness and GSM. Air permeability and water-vapour permeability also increased with increase in tencel fibre content. The anticipated increase in air permeability and relative water vapour permeability with increase in stitch length was observed. The thermal conductivity of the fabrics was generally found to increase with increase in the proportion of bamboo.

It is clear from the foregoing that, although a considerable amount of work has been done on bamboo blends and their properties, still there are many gaps existing in the literature, in particular, on thermal comfort, moisture management and spreading characteristics. Thus the manuscript addresses these issues and provides valuable information on the comfort characteristics of the blended fabrics for the first time. In the evolution of this manuscript, it became apparent that a considerable amount of work was needed to fill up the gaps existing in the literature and hence this work which deals with an investigation of the blend yarn properties and comfort properties of knitted fabrics was taken up.

This research work is focused on the thermal comfort parameters of knitted fabrics made from 100 per cent tencel yarn, 100 per cent bamboo yarn and tencel/bamboo blended yarns of different blend ratios.

The thermophysiological comfort of fabrics is prerequisite as customers covet adequate moisture, heat management-supported and UV protective clothing that measure up to their levels of activities and environmental conditions. Hitherto, scant tasks have been reported with the purpose of engineering both comfort and UV protection simultaneously. From that vantage point, the objective of this work is to develop a model for optimum UPF, air permeability, water-vapour resistance, thermal resistance, thermal absorptivity and areal density of knitted fabrics.

Weft knitted fabrics of various compositions were investigated. UPF was tested using the Labsphere UV transmittance analyser. The FX 3300 (Textest instruments) air permeability tester was used to test air permeability. Thermal comfort and water-vapour resistance were evaluated using the Alambeta and Permetest instruments, respectively. Based on image processing, the porosity was measured. Fabrics thickness and areal density were measured according to standard methods. Furthermore, parametric and non-parametric statistical test methods were applied to the data for analysis.

Linear regression was substantiated by Kolmogorov-Smirnov test. Then multiple linear regression of porosity and thickness together on UPF and comfort parameters were visually depicted by virtue of 3D linear plots. Residual analysis with quantile-quantile and probability plots, advocated the tests using the Shapiro-Wilk test. The result was validated by comparison with experimental data tested. The samples gave satisfactory relative errors and were supported by the z-test method. All tests indicated failure to reject the null hypothesis.

The predictive models were embedded into an interactive computer program. Fabric thickness and porosity are the inputs needed to run the program. It will predict the optimum UPF, areal density and thermophysiological comfort parameters. In a nutshell, knitters may use the program to determine optimum structural parameters for diverse permutations of UPF and thermophysiological comfort parameters; scilicet high UV protection together with low thermal insulation combined with low water-vapour resistance and high air permeability.

The paper aims to study changes in physical and mechanical properties of wind stoppers after fusing process.

Effect of fusing process on physical, mechanical properties of windproof fabrics for two types of windproof fabrics and four interlinings were studied. Properties including air permeability, drape, flexural rigidity, water vapor permeability, thickness, crease recovery and water repellency have been investigated.

It was found that fusing process and using interlining, improves flexural rigidity, crease recovery, drape and increases air permeability and water vapor permeability of the final assembly where as it has no effect on water repellency property of windproof fabric.

Wind stoppers are kinds of windproof and in some cases waterproof fabrics that have breathability property. They stop air penetrating fabric while letting water vapor pass through. One of the problems associated with garments made of these kinds of fabrics is lack of attractive appearance when worn. One solution to this problem is to fuse windproof fabrics with interlinings to increase flexural rigidity, drape, formability and serviceability or functionality. This study investigates effect of fusing process on main physical and mechanical properties of windproof fabric which may influence their performance besides aesthetic aspect.