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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 study aimed to determine the peak impact force and force attenuation capacity of weft-knitted spacer fabrics intended for padding that can be used for human body protection against impact.

A total of five weft-knitted spacer fabrics were fabricated with four different diameters of nylon monofilament yarns and one doubled monofilament yarns, respectively. The impact performances of the weft-knitted spacer fabrics were tested using a drop test method with a customized test rig to simulate falling. Impact tests were conducted on single- and multilayered experimental spacer fabrics to investigate the peak impact force and force attenuation capacity.

It was found that weft-knitted spacer fabric with a coarser or larger diameter of monofilament spacer yarn generated lower impact force and higher force attenuation capacity, thus resulting in better impact performance. Greater force attenuation can be achieved by utilizing a higher number of spacer fabric layers. However, the increase in thickness must be considered with the spacer fabric end use.

This study employed relatively coarse nylon monofilament yarn as spacer yarns to gain knowledge on the impact performance of weft-knitted spacer fabrics compared to warp-knitted spacer fabrics which are more common. The results showed that the diameter of spacer yarn significantly influenced the impact performance of the experimental weft-knitted spacer fabrics. These results could be useful for designing and engineering textile-based impact protectors.

Polyester multifilament is used to produce the face and back layer of warp knitted spacer fabric (WKSF) and these two layers are connected by polyester monofilament as a middle layer. This fabric has unique and extraordinary characteristics, and different possibilities of fabric structure and the middle layer thickness are tried to find out the moisture management properties. The paper aims to discuss these issues.

This study investigates the influence of fabric thickness and structure on moisture management properties.

Polyester monofilament quickly up takes the water molecule from the water reservoir and transfers it by capillary action. The gravitational force and the availability space between the two outer surface layers restrict the movement of water molecules, although the pressure develops to push the molecules from the water reservoir. As a result, all the spacer fabric samples attain the equilibrium state very quickly. WKSF and the hexagonal net structure prove to be better in vertical wicking.

The liquid movement is quick in the front side of the spacer fabric, and the rate of wicking is higher in open structure than in the closed structure. It confirms that the hexagonal net structure produces high pore size on fabric and it reaches maximum wicking values. Fabric thickness does not have much influence on the vertical wicking properties of all fabric samples, and the rate of liquid movement produces a similar trend. In in-plane wicking, the polyester monofilament in the middle layer of spacer fabric plays a major role rather than the outer surface layers of fabric.

This paper aims to summarize researches conducted related to functional textiles for prevention of pressure ulcers and critical analysis of the outcomes to pave path for the future research in this area for benefit of the patients. Pressure ulcers, also known as bed sores, pressure sores and decubitus ulcers, are localized areas of tissue damage that develop due to pressure usually over a bony prominence. A standard hospital mattress has an interface pressure of 100 mmHg which can result in pressure ulcers unless repositioning occurs at regular intervals. Moisture accumulation on the skin is an important physical factor predisposing a patient to the occurrence of pressure ulcers and tissue breakdown. The disability leads to several requirements of functional clothing and textile products. The textiles play a variety of roles in this concern, from simply having good aesthetic appearance to preventing life threatening risks. An ideal support surface prevents pressure ulcers by providing pressure redistribution and maintaining a healthy skin microenvironment. The use of the textiles for the care of elderly disabled and bedridden persons can play an important role, as their quality of life can be improved by making use of functional and good-looking textiles.

This review paper aims to summarize researches conducted related to functional textiles for prevention of pressure ulcers and critical analysis of the outcomes to pave path for the future research in this area for benefit of the patients.

In the past years, there have been several functional textiles developed for the prevention of pressure ulcer. They are designed to maintain proper microclimate around patient skin. Sheepskin is one of the oldest used bed overlays which prevent pressure ulcer but its prolonged use leads to uneasy feeling for the patient. A sensor in bed for pressure detection is one of the good alternatives as it provides proper indication on when to change the position of the patient so that the pressure can be shifted and ulcers is prevented. These sensors are costly and complex to setup so for common man they are not easily available. Multilayer textiles on the other hand are complex to make as the properties are dependent upon the fiber content, yarn structure, fabric structure and technique of layering them together. Spacer fabric provides good air and moisture permeability, but there is a scope to study this type of fabric by varying the fibers type and thickness of the spacer fabric. A bedding material which is not much complex and can be easily purchased and used by common man for in-house usage is the need of the hour.

There is no comprehensive review available regarding research in this area with critical analysis of the outcomes for future study.

Sewing is the most widely used and preferred method for manufacturing clothing products for extreme weather conditions and other industrial insulation systems. Multiple layers of functional fabrics in combination with insulation materials are used to thermally insulate precious body heat from its surrounding cold environment. The sewing process fixes the insulation material between the fabric layers. During conventional sewing, the insulation material is compressed along the stitch line. With the compression of the insulation material, entrapped air is forced to leave the insulation material internal structure, and heat loss occurs along the entire length of the stitch line. It results in the deterioration of thermal properties of the end product along the stitch line.

The amount of air, which is a decisive factor for thermal properties of any insulation system, was investigated at the level of a unit stitch length of a lockstitch. Conventional microscopy methods are not suitable to study the compression along the stitch line. With the help of X-ray tomography, the three-dimensional data of a stitch was taken and studied to measure the volume of air. The samples were prepared with conventional lockstitch sewing and a newly developed innovative sewing method “Spacer Stitching.” The results are compared with each other in terms of the amount of air present in a unit stitch length.

Calculations based on X-ray tomography images of lockstitch and spacer stitch revealed that, in the case of lockstitch, a unit stitch has a 15% of its volume made up of material and 85% of its volume by air. In comparison, the spacer stitch with the same sewing and fabric parameters has a material volume of 4.6 % and an air volume of 95.4% in a single stitch.

The research can positively improve the thermal properties of sewn material made for insulating purposes of conventional clothing as well as of industrial insulations.

There is no literature available which investigates and calculates the amount of air and material present along with a stitch line.

In experiments utilising sweat solution and distilled water, seamed ensembles performed less thermally efficiently than unseamed fabrics.

Water may not accurately reflect perspiration when testing multi-layered clothes for thermal comfort in wet state. Most researchers used water or sodium chloride (NaCl) to measure wet state thermal comfort. However, human perspiration is an extremely complex mixture of aqueous chemicals, including minerals, salts, lipids, urea and lactic acid. This study compares the effects of simulated sweat solution to distilled water on the thermal behaviour of a multi-layered fabric assembly with different seam patterns.

Experiment results show that stitching decreases thermal resistance and thermal conductivity. Seam pattern of 10 cm diagonal spacing is more thermally resistant than 2.5 cm diagonal spacing. In comparison to that of simulated sweat, fabric that has been moistened with distilled water exhibits increased thermal conductivity. Hollow polyester wadding or micro polyester wadding as the intermediate layer exhibits greater thermal resistance than multi-layered construction with spacer fabric as middle layer.

This study considers human perspiration while designing protective clothing for wet thermal comfort.

This paper aims to provide an overview of the current manufacturing methods for three-dimensional textile preforms while providing experimental data on the emerging techniques of combining yarn interlocking with yarn interlooping.

The paper describes the key textile technologies used for composite manufacture: braiding, weaving and knitting. The various textile preforming methods are suited to different applications; their capabilities and end performance characteristics are analysed.

Such preforms are used in composites in a wide range of industries, from aerospace to medical and automotive to civil engineering. The paper highlights how the use of knitting technology for preform manufacture has gained wider acceptance due to its flexibility in design and shaping capabilities. The tensile properties of glass fibre knit structures containing inlay yarns interlocked between knitted loops are given, highlighting the importance of reinforcement yarns.

The future trends of reinforcement yarns in knitted structures for improved tensile properties are discussed, with initial experimental data.

The casts sector is an important sector for orthopaedic textile products. Plaster and plastics casts are widely used in hospitals, pharmacies and health care centers, but they are heavy, not washable and do not offer a suitable fixation for bone fractures (e.g. hand wrist), especially when operated under different swelling conditions. After decreasing of the swelling, the cast is in a hard form and the stabilization effect of the cast is insufficient due to the occurring of distance between the skin and the cast. The purpose of this paper is to develop a new pneumatic cast that depends on Polyvinylchlorid coated fabric as an outer layer, skin friendly internal layers, an air chamber, and metal braces.

For more comfort, the cast is anatomically formed and the internal layers are made of cotton‐viscose fabrics and Polyester spacer fabrics. The pressure on the injured part can be controlled by using a pneumatic structure.

The characteristics of the developed pneumatic cast are found to be: easy to use, comfortable, washable, and light weight.

The paper describes the development of a new pneumatic cast that can overcome the difficulties of cast fixation with the injured part of the body: an economic product, that should be easy to use, light weight, comfortable, skin friendly, water resistant, easy to clean, and affordable.

Perspiration and heat are produced by the body and must be eliminated to maintain a stable body temperature. Sweat, heat and air must pass through the fabric to be comfortable. The cloth absorbs sweat and then releases it, allowing the body to chill down. By capillary action, moisture is driven away from fabric pores or sucked out of yarns. Convectional air movement improves sweat drainage, which may aid in body temperature reduction. Clothing reduces the skin's ability to transport heat and moisture to the outside. Excessive moisture makes clothing stick to the skin, whereas excessive heat induces heat stress, making the user uncomfortable. Wet heat loss is significantly more difficult to understand than dry heat loss. The purpose of this study is to provided a good compilation of complete information on wet thermal comfort of textile and technological elements to be consider while constructing protective apparel.

This paper aims to critically review studies on the thermal comfort of textiles in wet conditions and assess the results to guide future research.

Several recent studies focused on wet textiles' impact on comfort. Moisture reduces the fabric's thermal insulation value while also altering its moisture characteristics. Moisture and heat conductivity were linked. Sweat and other factors impact fabric comfort. So, while evaluating a fabric's comfort, consider both external and inside moisture.

The systematic literature review in this research focuses on wet thermal comfort and technological elements to consider while constructing protective apparel.

The warp-knitted fully-formed shorts are one kind of fully-formed garments knitted by a double-needle bar machine, which is widely used in the medical field. Because of its distinctive forming method, designers are unable to grasp the final effect of the product accurately during the design process. The purpose of this paper is to clarify a visible 3D simulation method in the design process along with the knitting method and structure characteristics, which is reflected in the final product effect.

This study introduces a simulation process for warp-knitted fully-formed fabric from an input 3D surface model group. Stitch mesh models are established according to the garment structure and the triangle index of the garment model that swchape-controlling points belong to is calculated. The garment model group includes a 2D plate and a 3D model, between which there is a space coordinate transformation relationship. The study makes use of the 3D tubes to connect the coordinate points in order and render the tubes in real yarn colors. The effects of two parameters, radial segment and tubular segment, are analyzed and decided to obtain a fine surface within a reasonable rendering time.

A stereoscopic simulation process from flat fabric to 3D product is realized using computer graphics technology. The warp-knitted fully-formed short is shown during the design process within a short time by setting the rendering parameters of tubular segments (ts = 125) and radial segments (rs = 6).

Visual simulation for the shorts provides a time-saving and resource-saving method for structure design and parameter modification before knitting. There is no need to knit samples repeatedly to satisfy demand, which indicates that it is a saver of time and resources.