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The purpose of this paper is to determine the validity and inter-/intra-laboratory repeatability of the first part of a novel, three-phase experimental procedure using a sweating Torso device.

Results from a method comparison study (comparison with the industry-standard sweating guarded hotplate method) and an inter-laboratory comparison study are presented.

A high correlation was observed for thermal resistance in the method comparison study (r=0.97, p<0.01) as well as in the inter-laboratory comparison study (r=0.99, p<0.01).

The authors conclude that the first phase of the standardised procedure for the sweating Torso provides reliable data for the determination of the dry thermal resistance of single and multi-layer textiles, and is therefore suitable as standard method to be used by different laboratories with this type of device. Further work is required to validate the applicability of the method for textiles with high thermal resistance.

This study provides the first “round-robin” data for measuring thermal resistance using a Torso device. In future publications the authors will provide similar data examining the repeatability of measurements that quantify combined heat and mass transfer.

The purpose of this paper is to develop multilayer clothing assemblies consisting of fibrous battings and reflective nano-fibrous thin layers for cold protective clothing for improved thermal insulation.

Thermal insulation values of totally 20 assemblies made of varying layers of a thick polyester batting and four different types of thin interlayers were measured using a guarded hot-plate to investigate the effect of the properties of thin interlayers and construction of multilayer assemblies on thermal insulation. Cold protective jackets filled with polyester battings sandwiched with or without interlayers were also made and tested on the sweating fabric manikin-Walter.

Results show that the Rosseland mean extinction coefficients of the thin interlayer and the associated radiative thermal conductivity of the interlayers have significant influence on thermal insulation of the assembly when more than one reflective nano-fibrous interlayers are sandwiched in the assembly. The cold protective jacket filled with multilayer polyester battings and reflective nano-fibrous interlayers have better thermal insulation and moisture permeability index (i_m) than those filled with the same multilayer polyester battings, but with non-reflective nonwoven interlayers or without interlayers.

This paper clearly demonstrates the advantages of reflective nano-fibrous thin material for interlayers in the cold projective jacket.

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.

The purpose of this paper is to analyze the effects of treatments using chitosan in different degree of deacetylations (DDs) on thermophysiological comfort properties of nylon 6,6/elastane pressure garments using a large skin model hot plate instrumentation to prevent infection and excess sweating during burn scar management for future designs.

Chitosans in different DD (DD 70, DD 81 and nylon 6,6/elastane fabrics in different structures, then the total DD 90) are treated with thermal resistance (R_ct) ((°ΔC)(m²)/W), total heat loss (Q_t or THL) (W/m²), apparent total evaporative resistance ( R e t A ), ((ΔkPa)(m²)/W), apparent intrinsic evaporative resistance ( R e f A ), ((ΔkPa)(m²)/W) and total insulation values (I_t) (clo) were analyzed using the large skin model hot plate instrumentation in comparison with untreated control samples. Antimicrobial activities, washing tests and moisture regain properties were also evaluated.

It is found that chitosan DDs have a significant effect on thermophysiological comfort properties of nylon 6,6 fabrics. A small but statistically significant decrease was observed in thermal resistance (R_ct) (Tog) and isolation (I_t) (clo) properties for higher chitosan DDs and for higher chitosan concentrations for all fabric samples after each treatment. Antimicrobial activity showed a small but statistically significant decrease for all samples with the increase of DD and fabrics treated with lower DD 70 of chitosan showed better antimicrobial activity for all samples. Additionally, fabrics treated with higher DD’s exhibited higher moisture regain.

Treatments with chitosan in different DD and in different concentrations impact the heat and moisture transfer properties of nylon 6,6 fabrics significantly. It is a reference to evaluate the thermophysiological comfort properties of pressure garments for future designs using dry and sweating skin tests while imparting antimicrobial activity with chitosans in different DDs.

The purpose of this paper is to investigate the influence and relationship of segment area and opening area in segmented protective pad in comparison to non-segmented pad to the energy absorption and performance attributes relevant to thermophysiological wear comfort.

The compressive stress-strain curves were obtained using Instron Tester and were used to analyse the energy absorption of the pads and the segmented pad assemblies. The dry thermal resistance and evaporative resistance of the non-segmented and segmented protective pads were obtained using MTNW Sweating Guarded Hot Plate.

The compression test results and performance attributes relevant to thermophysiological wear comfort test result demonstrated that the area segment and opening area of segmented pad influenced their energy absorption value, dry thermal resistance value and evaporative resistance value (permeability index value).

The results are expected to be useful for design and engineering of hip impact protective garments. Hip impact protective pads are used to prevent hip fractures in elderly people as a result of fall.

This paper aims to deal with the thermal resistance of multilayer nonwovens. The effect of fibre denier, cross-sectional shape and positioning within the layers were analysed with respect to the thermal resistance. Moreover, effect of compression on thermal resistance of the multilayer nonwoven structure have also be studied.

The study involves multiple layering of thermal bonded nonwoven webs and the effect of fibre denier and positioning of different nonwovens from the hot plate. To avoid the increase in thermal resistance because of the air gaps between layers, the nonwovens were enclosed within an acrylic frame to compress them to a thickness of 12 mm. Compressional behaviour of the nonwovens were tested at a rate of 5 mm/min with peak compressive load of 50 N. Multilayer nonwoven assemblies were tested for thermal resistance with compressive pressure of 3.5 gf/cm² and compared with that tested at zero pressure.

In the study, three-layered nonwoven structure, provided better thermal resistance than their single component counterparts. The structural characteristic of the multilayer nonwovens affected the conductive, convective and the radiative heat transfer. In a multi-layer nonwoven, the top most layer should have the finest fibre as possible. Second preference may be given to the middle and followed by bottom layers in terms of fibre fineness. However, fine solid fibres performed poorly in terms of compression and recovery resulting in poor thermal resistance under compressive load.

The experimental approach of controlling thickness while evaluating the thermal resistance will help in nullify the effect of air gaps between the layer interface, thus focussing on the effect of fibre denier and the positioning of nonwovens. This paper also discusses the unique properties of fine solid fibre and hollow fibres and their role in providing better thermal insulation for extreme cold weather applications.

This paper traces the evolution of objective measurement of textile hand and comfort from Pierce through modern methodology and approaches. Special emphasis is given to discuss the contribution of the Kawabata Evaluation System (KES) towards advancing the state of objective measurement. Laboratory case studies are used to show how data generated by the KES and other instruments can be integrated into a comprehensive approach that attempts to explain human comfort response to garment wear in terms of fabric mechanical, surface and heat and moisture transfer properties.

The purpose of this investigation is to measure seven different underwears on a sweating torso with differing relative air humidity (30, 50, 80 and 95 per cent RH) and at a fixed ambient temperature of 30°C to determine the influence of the water vapour partial pressure of the environment on the moisture transport properties of various materials.

All measurements in this investigation were accomplished with the authors' sweating torso which simulates the thermal‐ and humidity release of the human body. Four different sweating rates (50, 75, 100 and 150 g/h*torso) were selected for this investigation.

It was established that the partial pressure difference did not correlate directly with the evaporative cooling. In general, higher evaporation rates were observed in the dry climate conditions. However, with low‐sweat rates, the highest relative humidity (95 per cent) generally resulted in greater evaporative cooling than the lowest surrounding humidity conditions (30 per cent). In this investigation, a blended fabric made of PES/Vinal exhibited the most efficient evaporative cooling for all the sweat rates, as well as for the four relative humidity conditions chosen.

All received results are based on a surrounding temperature of 30°C (summer climate), for other temperatures the results may be different.

The investigation shows that both the relative humidity and the sweat rate have a major influence on the heat loss.

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.

This study examined the wear comfort and thermal insulation properties of Al₂O₃/graphite particle-imbedded sheath/core and dispersed fabrics via a thermal manikin experiment.

Al₂O₃/graphite sheath/core and dispersed polyethylene terephthalate (PET) yarn (POY 120d/24f) were spun using a pilot melt bi-component conjugated spinning machine, which was texturized as 75d/24f on the belt-type texturing machine. The woven fabric specimens were made using nylon 70d/34f in the warp with three types of weft yarn: Al₂O₃/graphite sheath/core, dispersed and regular PET yarns. Thermal insulation properties were measured and compared in terms of the heat retention rate (I) by KES-F7 apparatus and the maximum surface temperature by light heat emission equipment, as verified by the emissivity of various fabric specimens by far-infrared ray experiment. In addition, this study examined the thermal insulation (Clo value) characteristics of the clothes made of Al₂O₃/graphite sheath/core and dispersed fabrics using a thermal manikin apparatus, which were compared with the properties of regular PET clothing.

The thermal insulation of the dispersed fabric was superior to that of the sheath/core fabric, which was tentatively attributed to the higher emissivity of the dispersed yarn with Al₂O₃/graphite particles distributed over the whole yarn cross-section than that from the core of the sheath/core yarn. This result for the clothing measured using a thermal manikin was consistent with the higher heat retention rate (I) and the maximum surface temperature of the dispersed fabric than that of the sheath/core fabric. In addition, the thermal insulation of the dispersed and sheath/core fabrics was superior to that of the regular PET fabric, which revealed that the Al₂O₃/graphite particles imbedded in the dispersed and sheath/core yarns exerted a greater effect on the heat storage and release characteristics compared to that of the TiO₂ particles in regular PET yarn. The Clo values of the dispersed and sheath/core fabrics under the light-on condition were much higher than those under the light-off condition, and furthermore, the difference of the Clo value between the sheath/core and regular PET fabrics under light-on condition was approximately 1.7 times greater than that under the light-off condition. These results revealed that the far-infrared rays emitted from the Al₂O₃/graphite particles imbedded in the sheath/core and dispersed yarns enhance the heat storage and release characteristics from the fabric under the light-on condition, i.e. under the sunlight.

The previously examined thermal wear comfort properties of the various inorganic particle-imbedded fabrics were measured with the fabric state, not clothing, which could not provide objective data related to the actual wearing performance of clothing.