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The behavior of three raw cotton fabrics of different basic weaves and approximate yarn settings and yarn counts, when subjected to tensile deformation, is described in this article. The values of the breaking force in the fabric in the linen weave have the highest mean numerical value, while the cotton fabric in the atlas weave has the lowest values. The fabric in the twill weave has the highest values for elongation at break, while the lowest values are present in the fabric in the atlas weave. The fabric in linen weave is the most resistant to external deformations, while the fabric in twill and atlas weaves are the weakest. The standard deviation and coefficient of variation for fabrics in all weaves have values that move within a range that confirms the validity of the results. In some cases, larger variations of these statistical data mean that these results can be taken with a certain amount of caution. It seems that there are a lot of latent stresses in the fabric, which are relaxed during the action of the tearing force, causing greater variations in the measurement results. Deformation curves after nonlinear fitting of the breaking force-elongation at break dependence are described by polynomial equations of the fourth and fifth degree, with the fact that about 99% of the variability of the dependent variable can be explained by means of the analyzed independent variables. Polynomial models are practically usable because they can predict with high reliability the deformation behavior of fabrics with similar weaves in the direction of the warp. There are statistically significant correlations between numerous values for breaking force from the experiment and the polynomial model.

The article analyzes the equilibrium adsorption and thermodynamics of the process of removing a disperse dye from water using a sorbent based on cotton textiles waste. Sorbent is made from cotton knitted fabric waste after cutting, during the procedure of clothes production. The loss after washing of raw cotton waste, before transformation into adsorbent, is about 9%. The yield of sorbent made from washed raw cotton waste is just under 40%. The characterization of the new sorbent showed that there is porosity in the structure of the particles and that the chemical composition is dominated by carbon. Equilibrium adsorption was verified by three models, Freundlich and Temkin. The Freundlich equilibrium isotherm showed the best result, i.e. the fitting curve is closest to the experimental points. Since the staining takes place according to the mechanism predicted by the Freundlich model, a monolayer of adsorbed dye molecules is formed in the initial phase of adsorption. At the same time, more layers of adsorbed dye molecules are formed at non-specific sites on the sorbent through self-association of adsorbed dye molecules. The newly-adsorbed dye molecules can bind to the previously adsorbed molecules within the sorbent. The heat of adsorption, determined from Temkin's model, has values that assume that an exothermic process takes place during the adsorption of the dye on the sorbent.

In this paper, the ability of fabrics of different weaves and approximate fineness and density of threads to resist external forces of stress and deformation was investigated. An analysis of the influence of fabric construction on load behavior, i.e. on the behavior in use where the fabrics will be exposed to different types of stresses, is given. Two fabrics in plain and satin weaves were used. It was found that the structure and construction of fabrics directly affect the behavior during external stretching. The fabric in the plain weave has higher values for breaking strength and breaking elongation compared to the fabric patterns in satin weave. The pattern in the atlas weave has higher values for breaking elongation, which is related to the structure of the intertwining of the warp and weft and the residual stresses in the fibers, i.e. yarn. The fabric in the plain weave has higher values for the modulus of elasticity in both directions compared to the fabric in satin weave, which means that the initial deformation of the fabric in the plain weave requires a higher applied force compared to the fabric in satin weave. According to the results of work of rupture, the fabric in satin weave showed higher resistance to deformations compared to the fabric in plain weave. By modeling the force-elongation curve, using the second-order polynomial model, a very good coverage-fitting of the experimental data for both fabrics in the warp and weft direction is determined. Based on the model equations, the behavior of the same or similar fabrics in terms of mechanical characteristics can be predicted with sufficient reliability without practical measurement of breaking force and breaking elongation.

The possibilities of using an inexpensive sorbent for dyes removal from waste waters after textile dyeing were investigated in this work. Ashes from city heating plant that arise as a by-product in the burning process during the city central heating operated were sorbent. After chemical modification of the ashes it were transformed to the efficient sorbent. Based on the results from this paper, it can be said that the sorbent produced from ashes has potential for the textile dyes removal from aqueous solutions and emission reduction of toxic dyes. A metal complex textile dye was used and the adsorption thermodynamics were studied. On the basis of obtained results, it can be concluded that the natural sorbent is an efficient sorbent for metal complex removal dye from aqueous solution and has a potential for use on an industrial scale. Characterization of other similar, solid waste materials can help explain adsorbate–sorbent interactions in order to optimize and increase efficiency of adsorption process as an environmentally acceptable process. Negative values of free energy change indicate a spontaneous nature of adsorption, negative values of free enthalpy change indicate an exothermic adsorption process and negative values of free entropy change indicate a decrease of disordered system at solid – liquid interface during adsorption. Based on adsorption, kinetic and thermodynamic parameters it can be concluded that chemisorption of the dye on the sorbent is also present together with physical adsorption.

In this paper, new synthesized three azomethine derivatives applied in dyeing textiles checking the anti-microbial properties of active components, at the same time [1-3]. The emphasis is thrown on the verification of anti-microbial properties that are important for obtaining textile with significantly improved performance. All compounds were characterized and evaluated for their anti-microbial activity against 7 pathogenic bacteria, 1 parasitic protozoan and 1 fungus. It estimated anti-bacterial activity in vitro against the following microorganisms Staphylococcus aureus, Bacillus anthracis, Streptococcus faecalis, Enterobacter sp., Escherichia coli, Pseudomonas aeruginosa, Proteus mirabilis, and Candida albicans. The anti-amoebic activity in vitro was evaluated against the HM1: IMSS strain of Entamoeba histolytica and the results were compared with the standard drug, metronidazole. The synthesized azomethines, showed very good substantivity for wool fibers, gave fine coloring, with good degree of exhaustion after dyeing. The combination of extended synthetic analogues of natural molecules leads to discovery of chemical entities which might be excellent anti-microbial and anti-amoebic compounds as depicted in our results. Being highly the effects this compound can be explored in future as an option for decreasing pathogenic potential of infecting from different sources. Azomethines containing hydrazone (dyestuff 1) and phenylhydrazone (dyestuff 2) as moiety show average yield and moderate inhibition activity while azomethines containing thiosemicarbazone (dyestuff 3) as moiety show higher yield and greater inhibition activity towards gram-negative and gram-positive bacteria as well as a fungus.

The azomethines have broad applications in food and dyestuff industries, and in analytical chemistry, catalysis and also in the field of agrochemical. These have played an influential part in the improvement of modern coordination chemistry, but also they can also be found at key points in the development of inorganic biochemistry, catalysis and also in optical materials. The present paper describes coloring properties of wool fabric colored by new dyestuffs - azomethines, derivate of isatin. Synthesizing of dyestuffs can often have one to six chromogen, which can be defined as the photoactive components that contain colored or uncolored absorbent components. In addition of monoazo, diazo, poly-azo, anthraquinone, xanthan and similar systems, the azomethines or imines, also includes to the chromogen groups. Azomethines, such as, isatin-3-hydrazone, isatin-3-thiosemicarbazone and isatin-3-phenylhydrazone, were synthesized and their coloring performance on wool fabric assessed. The synthesized azomethines showed very good substantively for wool fibers with good coloring performance according to CIEL*a*b* system which characterized quantitative and qualitative coloring property. Dyestuff 3 or isatin-3-phenylhydrazone bound to woolen textiles to a greater extent and greater intensity (minimum value of L). Dyestuff 2 or isatin-3-thiosemicarbazone linked to the minimum amount for textiles (the largest value of L). Although it must be noted that it is a lighter shade (yellow color) as opposed to the dyestuff 3 (red color).

The influence of using formic, oxalic, citric, tartaric, hydrochloric, nitric, sulphuric and phosphoric acid for dyebath pH adjustment was investigated upon the dyeing of polyester fabric with CI Disperse Yellow 60. The positions of colour in CIELab coordinates of the samples dyed with the addition of tested acids were assessed and compared to those dyed with the addition of acetic acid. It was found that the differences in dyeabilities obtained with the addition of citric, oxalic, hydrochloric, nitric and sulphuric acid are entirely acceptable according to both M&S 83A and CMC (2:1) standards in comparison to the dyeability obtained with the addition of acetic acid.

In order to investigate the mechanism of adsorption of reactive dyes from the textile industry on ash from heating plant produced by brown coal combustion, some characteristic sorption constants are determined using Langergren adsorption equations for pseudo-fi rst and pseudo-second order. Combined kinetic models of pseudo-first order and pseudo-second order can provide a simple but satisfactory explanation of the adsorption process for a reactive dye. According to the characteristic diagrams and results of adsorption kinetic parameters of reactive dyes on ashes, for the applied amounts of the adsorbents and different initial dye concentrations, it can be concluded that the rate of sorption is fully functionally described by second order adsorption model. According to the results, the rate constant of pseudo-second order decreases with increasing initial dye concentration and increases with increasing amount of adsorbent – ash.

In dyeing process, the object is to transport or diffuse dyes and chemicals into the fibre. Various novel processes, including ultrasound, are being introduced and studied as more environmentally friendly alternatives. Encouraging results have been reported for the use of ultrasound energy in dyeing processes of micro-viscose. The recent studies revealed major ultrasound applications advances: savings of processing time, energy, chemicals, as well as environmental protection. Influence of various ultrasound frequencies (40, 200 and 400 kHz) on dyeing of micro-viscose knitted fabrics, by a reactive dye has been reported in this work. A method of reflection spectrophotometry has been employed to record reemission curves of the colored compounds. A software packet has been employed to calculate CIELab colored coordinates. Then, a comparison has been made with samples colored by conventional procedure according to CIELab76 and CMC (2:1) criteria. The use ultrasound in textile dyeing processing offers many potential advantages. The results prove better dye exhaustion by ultrasound and consequently the better fixing. The exhaustion for the bifunctional dye (containing two vinylsulphone groups) reaches 71.75 % without ultrasound, and 83.69 % with 400 kHz ultrasound. The 40 kHz, 150 W ultrasound causes a cavitation of higher intensity, compared to 200 and 400 kHz ultrasounds. In this particular case, destruction of cavitation bubbles is very intensive. That is why a large amount of cavitation energy is being transformed into a heat, yielding the additional bath heating. The ultrasounds with higher frequencies (200 and 400 kHz) cannot use such a strong power. The applied powering this case reaches 0.6 W. The cavitation bubbles are now smaller the cavitation disintegration is not so strong, and the energy loss is much smaller, i.e. a smaller amount of energy has been transformed into a heat. An ultrasound of an equal power, but of higher frequency contributes to the somewhat higher exhaustion and fixing. The ultrasound dyeing produces much obscured colours, compared the standard. The differences are evident and not negligible. The comparison of the samples treated ultrasound of different frequencies during dyeing revealed the higher coulours intensities with the increase of ultrasound frequencies of the equal power (200 and 400 kHz). However, the increase is not so expressed.

The dyeing of knitted fabrics made from 100 % cellulose using on-line procedure vinyl sulfonic reactive dye, with or without ultrasound energy, is carried out in this paper. The impact of temperature has been observed. The dye exhaustion is monitored using the method of absorption spectrophotometry, and the quality control of the coloration is monitored using color measurements. The acting of ultrasound on coloration consistency, as well as on some mechanical characteristics has also been examined. All examples of the ultrasound dyeing process show greater dye exhaustion in comparison to the conventional procedure. In addition, all the samples, which have been dyed with the ultrasound energy at 40°C, are significantly darker and have deeper color in comparison with the referent sample. The temperature has a great influence on kinetic energy of the dye molecules, and therefore on the diffusion processes in the dyeing system. The exhaustion chart indicates that when the temperature is lower the exhaustion degree drops. However, all the samples dyed with the ultrasound energy have bigger exhaustion. Besides that, ultrasound energy contributes to warming up the processing environment, so the additional warm up with the electricity is unnecessary, unlike the conventional way of dyeing. Since the reactive dyes chemically connect themselves with the cellulose substrate and in that way form covalent connection, the dyed fabrics have good washing consistency. Analysis results indicate that the consistencies are identical regardless the applied dyeing procedure. In other words, the dyeing method using the ultrasound energy produces the dyed fabric of the same quality. After analyzing the results of breaking force and elongation at break of knitted fabrics, it is noticeable that there is no degradation of previously mentioned knitted fabrics features (horizontally and vertically) during the ultrasound wave’s activity.