Factors Affecting Apparel Pattern Grading Accuracy: Existing Software Solutions Comparison and Development of New Solution

Every so often, grading is not 100% accurate due to the conventional system for calculating the grading incre¬ment. The aim of this study was to develop a new calculation system of grading increment provided by different software, e.g. Lectra, Gerber, Optitex, Boke CAD etc., and to develop a new mathematical solution that enhances grading precision. For this experiment, three different spec sheets of different buyers were collected, and then combined and drawn to a solitary sketch for both front and back including all points of measures (POM) for a more easy comparison. The solutions for the presence of diagonal and curve measurements were provided with examples using various tools and techniques of different professional garment CAD software. The benefit of the new approach is not only reduced errors of grading but also guaranteed garment fit without distorting style features. However, the drawbacks of the measurement method are complicated and time-consuming. They revolve around the fact that iterative fitting and adjustments are mandatory to improve the fit before bulk production. The study revealed that this new system slightly increases calculation time, whereas the sample approval time for order execution reduces considerably.

Electrical Resistivity of Conductive Leather and Influence of Air Temperature and Humidity

Leather is a material that has been used in different applications for centuries. Today, living in the era of high-tech¬nology, we are surrounded by smart products. For this reason, traditional products must be changed or im¬proved in order to support and make us more comfortable while using them. For instance, the touch screen display in electronics products is a smart phone’s or a tablet computer’s primary input device. Still, traditional leather will not function properly in a cold climate or other specific conditions. To make it conductive in such conditions, the double in-situ polymerization of the pyrrole coating method was used. The aim of this study was to observe the electrical properties of conductive leather. At the same time, it stands up to a wide range of different air temperatures, and relative and absolute humidity. These properties are essential because de¬signers and textile engineers should be familiar with them when they decide to use materials in different smart products. Electricity conductivity tests were carried out in year-round temperatures from 7.5 °C to 28.1 °C, with a relative humidity from 18% to 77% and a vapor air concentration from 2.77 g/kg to 12.46 g/kg. The so-called “multiple-step method” was used to test leather’s electrical resistivity for the first time. The method considers a material’s compressional properties and provides an indicator inherent for a material’s electrical properties, regardless of the mass and shape of samples. The results showed a strong dependence between water vapor air concentration and electrical resistivity, described using the formula ρ = 1.3103 H−1.04 Ωm, with a correlation coefficient of 0.87. There was no relation between relative humidity and electrical resistivity, and resistivity and air temperature. Also, the results confirmed again that changes in the shape of the sample used during tests did not influence the measurement’s results, but supported the appropriateness of the measuring method.

Adsorbent from Textile Waste for Removal of Textile Reactive Dye from Water – Equilibrium Adsorption and Kinetics

The removal of textile reactive dye from an aqueous solution on a new adsorbent prepared from waste cotton knitted fabric was investigated in this study. Waste cotton textile, used for the production of adsorbents, is a by-product of the cutting of stacked parts of cotton knitwear planned for the production of women’s T-shirts. The degree of efficiency of a paper pattern determines the amount of collected waste. The qualitative and quantitative characterization of the new adsorbent showed carbon and oxygen to be dominant in the chemical composition. A longer contact time means a greater amount of dye on the adsorbent, i.e. the dye concentration in the solution decreases with the duration of the adsorption process. The percentage of removed dye decreases with an increase in the initial dye concentration in the solution. However, the actual amount of adsorbed dye increases as the initial dye concentration increases. The results for equilibrium adsorption show that the Langmuir isotherm can be used for the interpretation of reactive dye adsorption on a new adsorbent. The pseudo-first order model can be fully used to describe the kinetics of dye adsorption on an adsorbent, with respect to valid results for statistical indicators. Based on the results, it can be concluded that the new adsorbent obtained from waste textiles has the potential to remove textile reactive dye from aqueous solutions.

Transfer and Friction Characteristics of Sports Socks Fabrics Made of Synthetic Fibres in Different Structures

Sports socks fabrics produced from polyester, polypropylene, their modified forms Thermocool®, Polycolon®, in three different structures (single jersey, piquet, terry) were investigated for their skin-fabric friction, permeability (air and water vapour), liquid absorption and transfer (absorbency, immersion, absorption capacity, wetback and drying) properties. According to the results, the effect of structure is dominant for frictional characteristics but focusing on the material, polypropylene created a bulkier and lighter structure with lower friction coeffi¬cients, an advantage for sports socks. The effect of structure is greater than the material also for some thermal comfort parameters, e.g. air permeability and absorbency. Focusing on materials, besides their better liquid transfer characteristics, modified forms of both fibres had worse performances for air permeability and absor¬bency compared to their standard forms. Absorption capacity, wetback and drying performances were related to fabric density besides the polyester’s higher regain capacity. While Polycolon® had superiority for wetback performance against standard polypropylene, this was not the case for Thermocool®; however, both modified materials showed apparent superiority for drying periods. Piquet structures were advantageous for absorption capacity and wetback performances for polypropylene. For sports socks parts, specific needs can be met by changing the fabric structure. Considering the materials, polypropylene and Polycolon® can be recommended for both thermal and tactile aspects.

Macro-Modelling of Rib-Knitted Tubular Parts

The aim of the research was to improve the process of knitted products design. The use of modern software helps us predict the physical and mechanical behaviour of materials, using their three-dimensional models. A macro-model of rib-knitted tubular parts was developed in the study. This model allows its implementation into algorithms, describing the peculiarities of the stretching process. Recent findings in the field of 3D modelling and simulation of knitwear behaviour aim at working with models of different scales of structural hierarchy. The use of macro-models provides the opportunity to simplify the geometry and significantly reduce the time required for simulation. Rib stitch structures are among the most popular weft-knitted ones. When using threads of usual stretchability (with breaking elongation that does not exceed 10–12%), the stretchability of some rib stitch structures in the course-wise direction can reach up to 350% and even more. When stretched in the course direction, rib-knitted stitches undergo a number of stages. The stretching process includes: decreasing the width-wise curling; mutual shifting of knit and purl stitches; reducing the curvature of the loop feet and loop heads; pulling the yarn from the loop legs to the loop feet; stretching of the yarn. The assumption was made that such parts of knitted garments as cuffs and borders on sweaters, cuffs on socks, where rib stitch patterns are used, can be described as thin-walled elastic shells. A part of a human body surface, covered with a rib-knitted garment part, can be approximated by a truncated cone. The mid-surface of the shell can be represented as a ruled surface created upon a set of Bezier curves, located along the circumference of the upper and lower bases of the truncated cone. The mathematical description, elaborated in the course of the research, was used for the computer program LastikTube, which was developed to create 3D macro-models of ribbed tubular garments.

Effect of Spinning Triangle and Production Speed of Hollow-Spindle System on the Bouclé Yarn Structure

This study aims to show the impact of both the width of the base of the spinning triangle and the production speeds of hollow-spindle spinning machines on the structure of ultimate multiple-thread-structure bouclé yarns and similar fancy yarns. A hollow-spindle spinning machine was used and bouclé yarns were made of a core thread, an effect thread and a (multifilament) binder. Initially, five bouclé yarns were made by setting the widths of the base of the spinning triangle at five levels, i.e. 4.5 mm, 7.5 mm, 10 mm, 13 mm and 16 mm. A further six bouclé yarns were made to show the changes that occur to the spinning triangle at various production speeds. The resulting fancy bouclé yarns were assessed by measuring the size, number and circularity ratio of bouclé profiles. It was found that at low production speeds, i.e. at start-up, that the spinning triangle was unstable, which adversely affected the structure of the final bouclé yarns. However, at production speeds higher than 17 m/min, the spinning triangle became stable, though such a stable spinning triangle had no impact on the structure of the resulting fancy bouclé yarns. The results of this study may help fancy yarn manufacturers to avoid making defective fancy yarns.

Necessary Parameters of Vertically Mounted Textile Substrates for Successful Cultivation of Cress for Low-Budget Vertical Farming

A growing population needs an expansion of agriculture to ensure a reliable supply of nutritious food. As a variable concept, vertical farming, becoming increasingly popular, can allow plant growth for local food produc¬tion in the vertical sense on, e.g. facades in addition to the classical layered structure in buildings. As substrates, textile fabrics can be used as a sustainable approach in terms of reusability. In our experiment, we investigated which properties a textile should possess in order to be suitable for an application in vertical farming by the example of cress seeds. To determine the best-fitted fabric, four different textiles were mounted vertically, and were provided with controlled irrigation and illumination. Our results showed that a hairy textile surface as provided by weft-knitted plush is advantageous. There, the rooting of cress plants used in this experiment is easier and less complicated than along tightly meshed, flat surfaces, as for woven linen fabrics.

Definition of the Main Features of Material Assemblies for Thermal Protective Clothing During External High-temperature Effect Modelling

A computational-experimental method of material selection for thermal protective clothing design is proposed in this article. The intended operating temperature of the garment lies within the range of 40−170 °С. The prereq¬uisite for the research was the lack of information regarding changes in the physical-mechanical and ergonomic characteristics of material assemblies during their use under high-temperature conditions. During the initial stage of research, there was a problem associated with the selection of the most important and the exclusion of the least significant indicators, in order to further reduce the number of experimental tests in laboratory and industrial conditions. The authors used the method of expert evaluations to solve the problems related to the selection of the most significant indicators for material assemblies. Material assemblies were formed by vary¬ing the combinations of heat-resistant, heat-insulation and lining layers of materials. Initial information for the proposed method was obtained from the experimental tests of sixteen material assemblies. According to the results of the ranking, the main parameters of material assemblies were identified as follows: the temperature range for which the use of clothing is intended, thickness, mass per unit density, rupture resistance, relative tear¬ing elongation, change in linear dimensions during mechanical loads, air permeability and change in assembly thickness during cyclic loads. It was established that the assembly that includes heat-resistant material of the Nomex comfort N.307 220 top, Nomex Serie 100 heat-insulation lining and Nomex TER 135 lining provides the necessary level of protection, reliability and ergonomics, and meets cost requirements.

High-Performance Fibres – A Review of Properties and IR-Spectra

High-performance fibres are fibre materials that exhibit at least one extraordinary property compared to con¬ventional fibre materials. That extraordinary property is frequently related to excellent fibre stability against certain influences such as fire, heat, chemicals or light. Also, a high mechanical strength is often a property of high-performance fibres. Nevertheless, it should be noted that high-performance fibres exhibit certain weak¬nesses in addition to their advantages. This review presents a broad overview of the most important high-per¬formance fibres, with a special emphasis on their chemical structure and related infrared spectra (IR-spectra). The categorization of the fibres according to chemical substance classes was performed to make it easy for the reader to find a fibre of interest. The main categories are polyethylene (PE) fibres, polyacrylonitrile (PAN) fibres, polyvinylalcohol (PVAL) fibres, polyester-based fibres, polyamide-based fibres, polyetheretherketone (PEEK) fibres, polyimide (PI) fibres, halogen-containing fibres, polyphenylene sulfide (PPS fibres), resin-based fibres and finally inorganic fibres. Competing materials are also discussed, and structural related materials can be easily identified. In addition to discussing fibre properties and selected applications, one of the main aims is to present a various number of IR-spectra as a tool for structural understanding and to help identify unknown fibres. Here, beside the IR-spectra of high-performance fibres, the reference IR-spectra of common fibres are presented for comparison.

Ukrainian Folk Ornaments in Modern Knitting

National arts and crafts are not only the skills of an individual nation but an ethnic phenomenon that has unique features and serves as a source of information on national history and culture. Decorative and applied art in Ukraine combines the traditions and techniques of manufacturing and decoration, which have been developed and passed down from generation to generation. It has a clear national identity and numerous regional differ¬ences in ornamental motifs, compositions and favourite colours. Therefore, the Ukrainian folk art has a significant potential and is a source of ideas in creating modern clothing as well as interior items. Embroidery as a way of creating ornamental motifs on a textile material using various techniques is a common process for decorating clothes and interiors for the Ukrainians. Today, ornamental compositions of embroidered folk textiles could be transmitted into modern clothes using various technologies. However, the use of a knitting machine allows creating a pattern during the item production. The ornament transformation into a pattern for knitting can be carried out with graphic software by creating a grid with a cell size similar to the loop size of a knitted structure for corresponding interlooping. A number of clothing and interior items with ethnic motifs was created using the capabilities of flat knitting machines within the masters programme “Knitting Technology and Design” at the Textile Technology and Design Department of the Kyiv National University of Technologies and Design.