The paper presents an extension of existed cover factor theory more suitable for the evaluation of light penetration through a net woven fabrics structure. It also introduces a new simplified model ...of predicting the ultraviolet (UV) protective properties of woven fabrics assuming that the coefficient of reflection (K
), transmission (K
), and absorption (K
) of constitutive yarns are known. Since usually they are not, the procedure of preparation of simulation of proper woven fabric samples without interlacing and with known constructional parameters is also presented. The procedure finishes with a fast and cheap detection of missed coefficient for any type of yarns. There are differences between theoretical and measured results, which are not particularly significant in regard to the purpose and demands of investigation.
The demand for hygienic nonwovens has increased, especially since 2020. As expected, the market for nonwovens showed an increase during the COVID-19 outbreak, especially in the medical and hygienic ...nonwovens sector. The aim of this study is to analyse the influence of the permeability properties of hygienic nonwovens that have been mechanically, chemically, and thermally bonded. Hygienic nonwovens are lightweight (from 20 to 120 g/m
), produced by carding (roller carding), and are bonded using three different bonding processes (mechanical, thermal, and chemical). Hygienic nonwovens are intended for protective clothing in hospitals. For the experimental part, the seven different nonwovens used for hygienic purposes were produced using the dry laying process. The samples were produced in Tosama, a factory for sanitary supplies. The research results show that the nonwoven bonding processes have a significant influence on the structural, mechanical, and permeability properties.
This paper deals with the possibility of a fast and accurate assessment of the number, size, and distribution of pores in transparent woven fabrics based on light penetration. The procedure of ...analyzing the pore structure in the fabrics based on a digital image is presented in detail. Fabric pores are treated as image particles and analyzed with the Java-based image processing software ImageJ. The obtained data relate to the constructional parameters of the fabric that allow for further analysis, provide the possibility to compare structurally similar or different samples as well as double check the results generated by optical or other means. This paper describes work on plain and similar to plain weaves. The conducted analysis revealed several expected and some unexpected results. Among the former, we can list the range of pore sizes in the examined woven fabrics, the distribution of pores in regard to their similarity, and the effect of dents. Examples of the latter are the magnitude of the cumulative percentage of pores in regard to the weave and the degree to which they participate in the inter-yarn and inter-fiber pores.
Knowing the reflection, transmission, and absorption properties of the yarns from which the woven fabric is made, prediction of a fabric’s UV-protective properties is simple. Using the geometrical ...properties of monofilament yarns and fabrics, which were determined optically, and following the cover factor theory, we have determined the areas of fabrics covered with no yarns, only one yarn, and two yarns. From a special selected set of high-module polyethylene terephthalate (PET) monofilament materials (e.g., fabrics), we have elaborated a method for determining the reflection, transmission, and absorption of yarns. By first defining the differently covered areas of fabrics, we were able to use them in a mathematical model for calculating and predicting the UV-protective properties of the fabrics. The calculated and measured values of the UV-protective properties of the selected test fabrics were highly correlated, with a correlation coefficient >0.98.
In this article, the breaking elongation properties of woven fabrics with incorporated PBT yarns are presented. Different polybutylene terephthalate (PBT) yarns (multifilament PBT yarn, cotton core ...yarn and twisted viscose yarn, both with PBT in the core) were used. Textured PBT yarns have latent elastic properties, which become visible after the thermal treatment by the finishing process. The aim was to determine which of the constructional parameters is most important in analysing the shrinkage of fabrics after treatment, breaking elongation properties of all tested fabrics, and breaking elongation properties of woven fabrics before and after treatment. A multivariate statistical method ANOVA was used for the analysis. The results show that treatment was by far the most influential factor in the study of breaking elongation of all tested fabrics. When analysing the fabrics separately before and after treatment, the construction of the PBT yarn and the weave were found to be statistically significant parameters.
Elasticity and recovery are important for clothing comfort, especially in the manufacture of apparel and sportswear. Recently, yarns containing PBT (polybutylene terephthalate), which are able to ...develop good elastic properties with high recovery after a finishing process (e.g., thermal treatment), have been used for this purpose. The aim of this work is to give a comprehensive overview of the use of PBT yarns in woven structure, with the aim of improving the elastic properties of cotton-like fabrics. The experimental part was divided into three main sequences to investigate the fabric properties (physical, elastic, UPF, comfort) influenced by (1) PBT-containing yarn structure, (2) weave and fabric structure (basic weaves and complex weaves) with PBT in weft direction, and (3) processing sequence-thermal treatment of PBT yarns or fabrics after weaving. According to the results, PBT-containing yarns have great potential for the production of lightweight elastic fabrics. The advantages of improving the elastic properties of fabrics by incorporating a relatively small amount of PBT yarns into the fabric only in certain areas, thereby minimally affecting the production costs, are demonstrated by a product with partially elastic areas obtained after thermal treatment.
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