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Öğe Determination of Color Removal and Fading Performance of Environmentally Friendly Chemical Alternatives to Hydrosulfite in Reactive Dyed Cotton Knitted Fabrics Depending on Dye Chromophore(Taylor and Francis Ltd., 2022) Atav, Riza; Çağman, F. Nilay; Şahin, Hatice; Çolakoğlu, ÖzgeAs is known, color stripping can be done with oxidizing or reducing agents. Today, reactive dye stripping is conventionally carried out via reductive method using hydrosulfite. However, from an environmental point of view, the use of more ecological chemicals has gained importance. In this study, it is aimed to determine the performances of reducing and oxidizing chemical alternatives to hydrosulfite, depending on the reactive dye chromophore. On the other hand, it was also aimed to provide a color fading effect on reactive dyed cotton fabrics with a treatment applied after dyeing. For this purpose, color stripping and/or fading effect was investigated on cotton knitted fabrics dyed with four different reactive dyes having anthraquinone (Reactive Blue 19), phthalocyanine (Reactive Blue 21), monoazo (Reactive Red 239) and metal azo (Reactive Red 23) chromophores. Studies were carried out with hydrosulfite, sodium hydroxymethane sulfinate and potassium persulfate at five different concentrations. It can be said that sodium hydroxymethane sulfinate and potassium persulfate can be used as an alternative to hydrosulfite in red dyes and blue dyes, respectively. COD and BOD values of wastewater of potassium persulfate treatment was found to be lower than hydrosulfite, which indicates that it is an ecological alternative over hydrosulphite. © 2022 Taylor & Francis.Öğe Determining the Permeability and Handle Properties of Wool, Yak and Cashmere Hand-knitted Fabrics(Taylor & Francis Inc, 2023) Unal, Pelin Gurkan; Atav, Riza; Ergunay, UgurLuxury fibers are used for their tactile properties, comfortable feeling for the users, and sometimes for status in society. These fibers are all protein-based and have always been compared to the properties of wool. Cashmere is known for its incredibly soft and warm yet lightweight and breathable qualities, making it a must-have fabric for any fall and winter closet. Besides labored and time-wasting cashmere production makes the fiber very expensive. Yak fiber is an alternative to expensive cashmere with similar properties, which costs only a quarter of cashmere. In this study, air and water vapor permeability properties, which are important for consumer comfort were investigated in addition to handle properties of the fabrics compared with the properties of the fabrics made of wool fibers. It was found that yarns made of wool fibers were easy to spin in fine yarn counts whereas yarns made of yak fibers were the coarsest. Hand-knitted fabrics made of cashmere fibers had the softest feeling even if the fabrics were produced with similar technical specifications. The permeability results of the fabrics were different, especially the porosity of the fabrics had a higher impact on the permeability of the fabrics.Öğe Dyeing of polyacrylonitrile knitted fabric using liposomes(Taylor & Francis Ltd, 2024) Atav, Riza; Koyluoglu, Selin Guler; Haji, Aminoddin; Ergunay, UgurIn this study, it was aimed to analyze the effects of liposomes on the dyeing of polyacrylonitrile fabrics. For this purpose, firstly liposome synthesis was carried out, and then liposome production was confirmed by Fourier transform infrared spectroscopy analysis. Additionally, zeta potential measurements were carried out to see whether stable structures were formed. Then, a selected basic dye was encapsulated with a liposome and the possibilities of using these capsules as alternative to retarders in the dyeing of polyacrylonitrile fabrics were examined. According to results obtained, it can be said that the 1% solution of synthesized liposomes creates a more stable suspension with a polydispersity index of 0.472 and the average particle size of 165.2 nm. On the other hand, it has been revealed that if 1% liposome is used in dyeing, a kind of retarder effect can be achieved in the dyeing of polyacrylonitrile fabrics. Moreover, it can be said that the decrease in color efficiency, that is, the loss of yield, caused by the use of liposome at the end of dyeing is lower compared to the retarder. This is also a very important issue, because a good retarder is expected to slow down the dye uptake, but not reduce the dye intake too much at the end of the dyeing. Dyeing levelness (%) was found to be 96.1, 97.4, and 97.1 for dyeings without auxiliary, with 1% cationic retarder and with 1% liposome, respectively. Beyond this, no significant difference was observed in terms of fastness of dyeing.Öğe Eco-Friendly Ozone Process for Denim Garments as an Alternative to Conventional Bleaching(Korean Fiber Soc, 2024) Atav, Riza; Gunduz, Oner; Yaz, Sercan; Cakan, Gizem; Sevgili, BahadirhanIn recent years, sustainability has become an important issue in production. The denim industry is environmentally problematic as an area where a wide variety of chemicals are used. Therefore, it is of great importance to replace various chemicals with clean technologies such as ozone. In this study, it was aimed to determine the effects of water content, treatment time and pH on both color fading and strength of the fabric during ozone treatment of denim textiles. Thus, optimum conditions of color fading with ozone in industrial applications have been revealed. It was found that it is most appropriate to work at 30% water content and the ozonation time should be changed according to the desired degree of color fading. Furthermore, it can be said that there is no significant difference between pH 4 and pH 7, but pH 11 is significantly different from them and the best color fading is obtained at pH 4. Since there is no significant difference between pH 4 and pH 7, it is thought that the pH 7 condition, which is simpler in practice and does not require the use of chemicals, would be optimal.Öğe Effect of chromophore type on efficiency of reactive dye removal using polyamidoamine dendrimer(Wiley, 2024) Atav, Riza; Akkus, Eray; Cifci, Deniz Izlen; Ergunay, Ugur; Gunes, Yalcin; Gunes, ElcinIn this study, by selecting a sample of dyes from a wide variety of chromophores used in the production of reactive dyes (monoazo, bisazo, metal azo, phthalocyanine, anthraquinone, copper formazan and triphendioxazine), the colour removal performance of polyamidoamine (PAMAM) dendrimer in reactive dyes was statistically evaluated depending on the dye chromophore groups (and accordingly molecular weight and number of sulfo groups of the dye), dendrimer concentration and centrifugation time. When all the results were examined, it was observed that the colour removal efficiency was significantly lower in metalazo and copper formazan-based reactive dyes, whereas colour removals ranging from 93% to 98% could be obtained in bisazo, triphendioxazine, monoazo, anthraquinone and phthalocyanine dyes. With the use of dendrimer, the best colour removal efficiencies occurred at pH 3. However, it was found that the centrifugation time of 15 min is sufficient for all dyes, and a longer centrifugation does not provide any additional benefit in terms of colour removal.Öğe Environmentally Friendly Coloration of Polyamide Fabrics with the Use of Natural Dyes: A Study Including Results of Industrial Scale Applications(Korean Fiber Soc, 2024) Atav, Riza; Soysal, Selma; Haji, AminoddinIn recent years, it is seen that there have been many publications on natural dyes in literature. In the studies carried out, one or more plants were taken and the color and fastness obtained with them in the presence of different mordants were examined. Beyond that, functionalities such as odor, antibacterial activity, and UV protection that natural dyes impart to the fabric were examined. However, the important thing that the literature needs is to represent also the results related to the industrial scale production since industry shows high interest to be able to use natural dyes. In this study, seven plant dyes have been used for the coloration of polyamide fabric. The studies have been conducted both on an industrial scale and at the laboratory scale. Based on the statistical analyses, four dyes with the highest color strength and fastness properties including catechu, madder, mulberry leaf, and pomegranate peel were selected for more studies on industrial scale. The results confirmed the good color strength and satisfactory fastness properties against repeated washing, rubbing, water, and perspiration for all selected dyes. The samples dyed with those dyes exhibited excellent protection against UV radiation. The results obtained in this study showed the potential of the selected natural dyes in eco-friendly industrial dyeing of nylon fabric with acceptable fastness properties.Öğe Enzymatic coloration of polyamide fabrics and its comparison with conventional dyeing(Wiley, 2024) Atav, Riza; Karagoeren, Ece; Soysal, Selma; Yakin, IsmailAmong the textile wet processes, the colouring process is the process step that causes the most environmental pollution. New approaches that support sustainable production instead of environmentally harmful processes are extensively researched in the literature. When considering substitution of chemical processes with environmentally friendly methods, one of the issues that comes to mind is enzymatic processes. It is noteworthy that in recent years, interesting and promising studies on the use of laccase enzymes in textile dyeing have been published in the literature. However, studies on enzymatic colouring are still very limited and sufficient success has not been achieved especially on polyamide. The aim of this study is to develop an environmentally friendly enzymatic dyeing method, which can be an alternative to dyeing polyamide knitted fabrics with 1:2 metal complex dyes according to the exhaustion method. For this purpose, various phenol and amine compounds, and their mixtures were used as precursor, and the colours that can be obtained by enzymatic colouring have been determined. In addition, optimisation of enzymatic colouring conditions (enzyme concentration, temperature and time) was carried out for the precursors that gave the best results in terms of colour and fastness. Furthermore, enzymatic dyeing was compared with conventional 1:2 metal complex dyeing in terms of technical and economic aspects. The reaction pathways in enzymatic coloration with laccase enzyme by using various precursors were also explained by Fourier-transform infrared (FTIR) analysis.Öğe Enzymatic coloration of wool fabrics and its comparison with conventional dyeing(Wiley, 2024) Atav, Riza; Karagoz, Gokmen; Ergunay, UgurThe search for a more ecological alternative to dyeing processes, which is the most polluting textile process, has become one of the most studied topics today. In this respect, enzymatic colouring with the use of laccases offer important opportunities, but studies on enzymatic colouring are still very limited. However, in order for enzymatic dyeing to find industrial-scale use, the colour variety must be wide. Within the scope of this study, it is an important output that this study has brought to the literature, that the variety of colours that have been obtained in the literature in enzymatic dyeing has been increased so far by working with a wide variety of precursors and their mixtures, including those that have not been tested on wool before. At the same time, the reaction mechanism of the enzymatic dye synthesis and the chemical structures of the dyes were elucidated by Fourier-transform infrared spectroscopy. Beyond that, as it is known, when a new dyeing process is developed, its technical, economic and ecological advantages and disadvantages compared to the currently accepted conventional dyeing should be revealed. In this study, the colours obtained by enzymatic dyeing were matched with 1:2 metal complex dyes and then two fabrics dyed with the same colour, one enzymatic and the other with conventional method, were compared in terms of technical (colour, fastness), economic (water, energy and chemical consumption) and ecological (biological oxygen demand of wastewater, chemical oxygen demand, etc.) aspects.Öğe Inclusion complexes of ?-cyclodextrıne with Fe3O4@HA@Ag Part II: Their use in the production of PVP nanowebs(Inst Natl Cercetare-Dezvoltare Textile Pielarie-Bucuresti, 2023) Atav, Riza; Agirgan, Ahmet Ozgur; Yildiz, Aylin; Bayramol, Derman Vatansever; Erguenay, UgurHumic acid is a material formed as a result of the degradation of animal and plant wastes, it cleans heavy metals which are industrial wastes that threaten both the environment and human health. In part I of this study, the Fe3O4@HA@Ag compound was synthesized, its inclusion complex with beta-cyclodextrin was prepared by using the kneading technique and obtained inclusion complexes were characterized. In this study, part II, nanowebs were formed from the inclusion of complex-containing polymer solution via the electrospinning method. The electrospinning solution consisted of beta-CD:Fe3O4@HA@Ag inclusion complexes at the rate of 5%, 7.5% and 10% by weight and the polyvinylpyrrolidone (PVP) polymer as the carrier. The obtained nanoweb material was characterized by instrumental methods such as SEM, FTIR, XRD, and TGA. The results obtained from FTIR, XRD and TGA revealed that beta-CD:Fe3O4@HA@Ag inclusion complexes containing nanowebs were successfully produced. The uniform fibre formation was detected from SEM images. The average fibre diameter of 5%, 7.5% and 10% beta-CD:Fe3O4@HA@Ag inclusion complex containing nanowebs were measured to be 612.5 nm, 610.8 nm and 431.2 nm, respectively.Öğe Investigation of the application angle and mode parameters on colour fading obtained in laser process(Wiley, 2024) Atav, Riza; Gunduz, Oner; Yaz, Sercan; Cakan, GizemIn this study, the effect of four factors affecting colour fading in the laser process (resolution in the X direction, resolution in the Y direction, pixel time and application direction/angle [56 degrees, horizontal, vertical]) were statistically examined. Then, the effect of application direction/angle (56 degrees, horizontal, vertical) and application mode (Normal, HDR Soft, HDR Medium) were investigated in more detail. It is believed that this study will contribute to the literature and is original since there is no study on the effect of application angle and/or mode during laser treatment. It was found that beyond the resolution and pixel time, application direction/angle and mode (HDR Medium > HDR Soft > Normal) are important in terms of colour fading for 11.25 ounce trousers made of 95.3% cotton/3.4% polyester (T400)/1.3% elastane used in this study.Öğe Investigation of the dyeability and various performance properties of fabrics produced from flax and hemp fibres and their blends with cotton in comparison with cotton(Wiley, 2024) Atav, Riza; Dilden, Durul Busra; Keskin, Seda; Ergunay, UgurIn this study, it is aimed to provide alternative fibres to cotton with enhanced comfort level, environmentally friendly and colour-enriched in the cellulosic knitted fabric field. For this purpose, in addition to 100% cotton, 100% linen, 100% hemp yarns, knitted fabrics were produced from 70% cotton/30% linen and 70% cotton/30% hemp yarns. First of all, the properties of yarns such as tenacity, elongation at break, yarn unevenness, thin places, thick places and neps were examined comparatively. Then, pique fabrics were produced from these yarns and dyed with a reactive dye to a selected colour. Afterwards, physical (weight, wale/course density), mechanical (bursting strength, pilling, abrasion resistance) and comfort (air permeability and water vapour permeability) properties of all fabric samples, both in raw form and after dyeing and finishing processes, were compared. Furthermore, dyeing properties (colour, dye-uptake, dyeing levelness, fastness) of fabric samples were also investigated. The dye uptake (%) values of the yarns decrease in the order of cotton > cotton/hemp > cotton/linen > hemp > linen. However, fastness values of dyed fabrics were nearly identical. Physical and mechanical properties of fabrics were very similar, while the air permeability of the fabrics decrease in the order of hemp > linen > cotton/hemp > cotton/linen > cotton. As a result of the study, it has been possible to produce knitted fabrics with superior performance characteristics (dyeability, comfort, etc.) from yarns produced via blending natural cellulosic fibres (flax and hemp) with certain proportions of cotton fibres, which contribute to sustainable production.Öğe Investigation of the Dyeability of Cotton Fabrics with a Halochromic Dye According to Exhaust and Padding Methods(Taylor and Francis Ltd., 2022) Atav, Riza; Akkuş, Eray; Ergünay, UğurSmart textiles are an important field in textile since these products are high-added value. One of the applications of smart textiles is chromic textiles, which can be used as a sensor. As is known, exhaust and padding dyeing are the basic methods and for this reason in this study process optimization for application of a halochromic dye (bromcresol purple) to cotton by these methods was carried out. According to experimental results, it can be said that dyeings according to exhaust method using wool dyeing process was successful for cationized cotton. On the other hand, pigment dyeing process used by garment dyers did not give satisfactory results in terms of fastness. In addition, the optimum conditions for padding method were determined as 5 g/L dye and 20 g/L binder. Fabrics showed very good color changing ability with regard to pH both with acid-base solutions and acid-base vapors. Accordingly, it can be said that both exhaust and padding methods can be used for dyeing with halochromic dyes, if optimum conditions are determined. © 2021 Taylor & Francis.Öğe Laser-Activated Organic Bleaching Process as an Environmentally Friendly Clean Alternative to Permanganate Bleaching in Denim Washing(Korean Fiber Soc, 2023) Atav, Riza; Gunduz, Oner; Yaz, Sercan; Cakan, Gizem; Sevgili, BahadirhanToday, sustainable production has become an important concept. As the trends in the world bring about the widespread use of used-looking clothes, it has become mandatory to apply processes such as spray rodeo, which is the process done by spraying permanganate with a special spray gun or applying it with a brush to the desired area. However, permanganate has risk of causing irritation to the face and eyes, and cough, mucosal irritations, shortness of breath, etc. Therefore, it is of great importance to replace permanganate with clean alternatives. In this study, it was aimed to obtain high bleaching efficiency via laser-activated organic bleaching process and thus to obtain permanganate-like results in a sustainable way. It was found that the effects of organic bleaching agent concentration and pixel time on the degree of color fading are statistically significant and the optimum color fading could be achieved at 30% bleaching agent concentration and 300 & mu;s pixel time. However, the bleaching agent concentration and/or pixel time can be changed according to the desired degree of color fading. Results indicated that by using laser-activated organic bleaching process, it is possible to obtain nearly same color fading effects with that of permanganate bleaching, which means a cleaner alternative has been developed.Öğe Luxury animal fibres: Part 1: Hair fibres from goats(Nova Science Publishers, Inc., 2023) Atav, Riza; Hunter, LawranceLuxury animal fibres, the subject of this book, are related to the niche product area covering low volume big value-added products. Detailed information on luxury animal fibres, is still very limited even though the number of publications on luxury animal fibres have increased in recent years. In this book, after giving an overview of the luxury animal fibres, detailed information is given about the mohair, cashmere and cashgora fibres obtained from animals belonging to the goat family. Firstly, a general introduction is made about the animal that is the source of that fibre and the fibre it gives, and then information about historical background, world production, factors affecting production and yield, classification, microscopic properties, physical properties, chemical properties and end-uses of the fibre in question is given. It was mainly followed the way of explaining the general properties of luxury fibres, as much as possible rather than summarizing the literature even if in some cases it was done so. Although there are several valuable resources in this field, the most important factor that distinguishes this book from others is that it deals with the diverse field a very systematic and comprehensive way for each fibre. In this way, the book is considered to be useful in terms of solving the problem of readers accessing information on various aspects related to luxury hair fibres obtained from animals belonging to the goat family. © 2023 by Nova Science Publishers, Inc. All rights reserved.
